Roseate spoonbill: Difference between revisions

From Indian River Lagoon Project
mNo edit summary
mNo edit summary
 
(45 intermediate revisions by the same user not shown)
Line 1: Line 1:
<div class="irlbody">
<div class="irlbody">
{{IRL header biota}}
{{IRL header estuary|cat=Biota}}
<p class="irlsubtitle">Tag Line</p>
<div class="irlcontenttop">
[[File:Roseate Spoonbill (Platalea ajaja) (30675303153).jpg|320px|thumb|alt=Roseate Spoonbill (Platalea ajaja)|'''Roseate spoonbill'''<br/>''Platalea ajaja''<br/>Status: [[:Category:Endangered Species|State Threatened]]]]
The Roseate spoonbill (Platalea ajaja) is a medium-sized, pink-bodied, wading bird with a flat spatula-shaped bill. They are found in the southeastern United States and West Indies through Mexico and Central America to South America. The Roseate spoonbill is the only spoonbill native to the Western Hemisphere and the only pink bird that breeds in Florida. Spoonbills can be seen within the [[Indian River Lagoon Estuary|Indian River Lagoon National Estuary]] at the [[Merritt Island National Wildlife Refuge]] in Titusville, Florida.
 
Roseate spoonbills feed by sweeping their spoon-shaped bills side to side, often sifting through mud as they walk through shallow water. Their diet includes small fishes and aquatic {{Define|invertebrate}}s, as well as some plant material. They are found in coastal marshes, {{Define|lagoon}}s, mudflats, and {{Define|mangrove}} keys, foraging in salt, fresh and {{Define|brackish}} water. Flocks typically include fewer than half a dozen individuals.
 
Spoonbills reach maturity at approximately 16 weeks. Females typically lay two to five brown-speckled white eggs, which hatch after about 24 days. In about eight weeks, the young roseate spoonbills are ready to fly.<ref name="tpwd" />  Spoonbills can live up to 15 years in human care and an estimated 10 years in the wild.<ref name="natzooroseate" />  
</div>
</div>
<div class="irlcontentmiddle">
==Appearance==
Roseate spoonbills have pink wings and underparts (with some red on the tops of the wings) with a white neck and back, and pinkish legs and feet.<ref name="fwcroseate" /> They can reach a length of 30-40 inches with a wingspan of 50-53 inches<ref name="fwcroseate" /> and weigh up to 4 pounds.<ref name="fwsdarlingroseate" />


<div class="irlcontenttop"><!-- Content Top div -->
The pink coloration of spoonbill feathers is caused by an abundance of carotenoids, or algae pigments, present in the food the birds eat. As the spoonbill ages, the carotenoids accumulate from all of the aquatic animals it has eaten and the pink coloration becomes darker.<ref name="fwsdarlingroseate" /> No other Florida species is similar. The roseate spoonbill is the only spoonbill native to the Western Hemisphere and is the only pink bird that breeds in Florida.<ref name="fwcroseate" />
The colonially nesting Roseate Spoonbill (Platalea ajaja) is a medium-sized, pink-bodied, ibis-like bird with a flat spatula-shaped bill. These birds are found in the southeastern United States and West Indies through Mexico and Central America to South America, where they are distributed south to northern Argentina east of the Andes and in western Ecuador and northwestern Peru west of the Andes.  


Throughout much of their range, the species is apparently declining as a result of habitat alteration, hunting, and pollution. In the United States, Roseate Spoonbills were common along the Gulf Coast in the early 19th Century, but were almost exterminated in the 1930s by intense persecution and destruction of wading bird colonies for the plume trade starting in the 1880s.  
==Distribution==
[[File:2019-02-15 074 Roseate spoonbill (Platalea ajaja) at Sian Ka'an Biosphere Reserve, Mexico.jpg|320px|thumb|right|alt=Roseate spoonbill (Platalea ajaja) in flight|Spoonbill in flight]]
The roseate spoonbill has an incredibly large distribution across the Americas, with its residential, or non-breeding, range spanning Argentina and Chile northward to the Texas Gulf Coast and Florida.<ref name="huey" /> There has never been a sighting outside of the Americas.<ref name="Dumas2000" />


They were legally protected in the 1940s, after which populations recovered somewhat, but declines apparently followed later in the 20th century as a consequence of mosquito control programs and alteration of breeding and feeding habitats.  
In the winter, U.S. populations are restricted to the southernmost regions of the Gulf Coast, primarily in south Florida, southwest Louisiana, and coastal Texas.<ref name="Dumas2000" /> In Florida, the species is found in Florida Bay, Tampa Bay, and Brevard County.<ref name="fwcroseate" />


These highly gregarious waders feed by sweeping the bill side to side, often sifting through mud as they walk through shallow water. Their diet includes small fishes and aquatic invetebrates, as well as some plant material. They are found in coastal marshes, lagoons, mudflats, and mangrove keys, foraging in both salt and fresh water. Flocks typically include fewer than half a dozen individuals, but they are often associated with other wading birds as well.  
Although their range is poorly documented in South America, spoonbills are known to inhabit some portion of each South American country at some time of year.<ref name="iucn" /> Unlike the spoonbills of the U.S., the spoonbills in South America tend to prefer living and nesting inland around freshwater.<ref name="Dumas2000" /> Some believe the South American populations are distinct from the resident populations in the USA and Central America.<ref name="Dumas2000" />


In courtship, male and female spoonbills first interact aggressively, then perch close together, presenting sticks to each other and crossing and clasping bills. They typically nest in mangroves or other trees and shrubs 5 to 15 feet above ground or water, but sometimes nest on the ground. The nest, a bulky platform of sticks with a deep twig- and leaf-lined center, is built mainly by the female with material brought by the male,  
As for breeding range, in the U.S., the roseate spoonbill breeds along the coasts of Texas, Louisiana, and southern Florida. Outside of the U.S., spoonbills only seem to breed along the coasts of Mexico and Central American countries.<ref name="howell" /> Little information on the spoonbills breeding range is available in Central and South America.<ref name="Dumas2000" />
 
Clutch size is 2 to 3 eggs, (range 1 to 5). The white eggs are spotted with brown. Eggs are incubated (by both sexes) for 22 to 24 days. Both parents feed the young. Young may leave the nest after 5 to 6 weeks and are capable of strong flight at around 7 to 8 weeks. .Roseate Spoonbils are mostly silent, but make a soft froglike croak when disturbed. (Matheu and del Hoyo 1992; Kaufman 1996; AOU 1998; Dunne 2006)


==Behavior==
==Behavior==
[[File:Roseate Spoonbill - Myakka River State Park.jpg|320px|thumb|right|alt=Roseate Spoonbill (Platalea ajaja)|Roseate Spoonbill (Platalea ajaja)]]
Roseate spoonbills forage using tacto-location to locate food while wading through shallow, muddy waters. In the early mornings and evenings, they slowly walk with their bill partially submerged, swinging it side to side, to sift out food from mud and water. The mandible contains nerve endings that snap the jaw shut as it contacts prey.<ref name="Dumas2000" />


The behavior of roseate spoonbills is not well documented. There is very little quantitative information and what is documented is not well understood.<ref name="Dumas2000" /> Some breeding behaviors have appeared similar to that of other spoonbills, but further research into the behavior of roseate spoonbills and taxonomic relationships between spoonbills needs to be done.<ref name="Dumas2000" />
Catching prey by feeling, roseate spoonbills are able to forage without light, and thus their eye structure is not highly developed.<ref name="rojas" /> Roseate spoonbills eat smaller prey. This includes fish such as minnows and killifish; {{Define|crustacean}}s such as shrimp, crayfish, and crabs; aquatic insects; mollusks; slugs; and plant material such as roots and stems.<ref name="audubonroseate" /> If needed, roseate spoonbills may beat prey against a hard surface to aid in digestion .<ref name="arkive" />


Roseate spoonbills forage using tacto-location to locate food while wading through shallow, muddy waters (National Audubon Society 2014).<ref name="Dumas2000" /> In the early mornings and evenings, they slowly walk with their bill partially submerged, swinging it side to side, to sift out food from mud and water (Smithsonian n.d.; National Audubon Society 2014). The mandible contains nerve endings that snap the jaw shut as prey comes into contact with it (ARKive n.d.).
Roseate spoonbills preen using their bill to nibble and run down the length of each feather, starting with their lower neck and down to their breast and abdomen. They clean their bill by dipping the tip in the water and then shaking their head to dry the bill.<ref name="Dumas2000" />  
 
Catching prey by feeling, roseate spoonbills are able to forage without light, and thus their eye structure is not highly developed (Rojas et al. 1999). Roseate spoonbills eat smaller prey. This includes fish such as minnows and killifish; crustaceans such as shrimp, crayfish, and crabs; aquatic insects; mollusks; slugs; and plant material such as roots and stems (National Audubon Society 2014). If needed, roseate spoonbills may beat prey against a hard surface to aid in digestion (ARKive n.d.).
 
Roseate spoonbills preen using their bill to nibble and run down the length of each feather, starting with their lower neck and down to their breast and abdomen.<ref name="Dumas2000" /> They clean their bill by dipping the tip in the water and then shaking their head to dry the bill.<ref name="Dumas2000" />  


Sleeping occurs communally with the roseate spoonbills standing on one leg, with their head turned backward underneath feathers in their upper back.<ref name="Dumas2000" />
Sleeping occurs communally with the roseate spoonbills standing on one leg, with their head turned backward underneath feathers in their upper back.<ref name="Dumas2000" />


Members within a flock have been seen having a sham battle.<ref name="Dumas2000" /> This interaction does not harm either fighter, and it is unknown why this behavior is done. In the sham battle, two birds fly at each other, and may rise about a meter off the ground as they beat their wings.<ref name="Dumas2000" />
Members within a flock have been seen having a sham battle. This interaction does not harm either fighter, and it is unknown why this behavior is done. In the sham battle, two birds fly at each other, and may rise about a meter off the ground as they beat their wings.<ref name="Dumas2000" />


When faced with a threat, roseate spoonbills alert conspecifics by standing tall with their neck outstretched and head held high.<ref name="Dumas2000" /> An alarm call may come in addition with this stance to call further attention to the threat. When fighting a threat, they hold the axis of their body parallel to the ground with their head lowered, neck outstretched, and wings raised above their body.<ref name="Dumas2000" /> Striking with their bill may result if the threat is intensified. One threat that causes this kind of behavior includes territorial defense against an encroaching member of an outside flock.<ref name="Dumas2000" />
When faced with a threat, roseate spoonbills alert the colony by standing tall with their neck outstretched and head held high. An alarm call may come in addition to this stance to call further attention to the threat. When fighting a threat, they hold the axis of their body parallel to the ground with their head lowered, neck outstretched, and wings raised above their body. Striking with their bill may result if the threat is intensified. One threat that causes this kind of behavior includes territorial defense against an encroaching member of an outside flock.<ref name="Dumas2000" />


Courtship for roseate spoonbills involves ritualized exchanges of nest material such as sticks and twigs from the male to the female to attract her and help her build a deeply cupped nest in vegetation above a water source (Smithsonian n.d.; TPWD n.d.). Males may head-bob and shake the stick as they deliver nesting materials to a female.<ref name="Dumas2000" /> Females have been seen to beg for nesting materials with a bowing display.<ref name="Dumas2000" />  
Only males have been seen to use defense mechanisms to defend a wide territory around his nesting site.<ref name="arkive" /> Defense mechanisms may include a threat posture and chasing other spoonbills. Males will give up their territory rather than fight if threatened by other species. Females will only defend the actual nest.<ref name="Dumas2000" />


During courtship, the male and female first interact aggressively toward one another, but then proceed to perch close together with their bills crossed as the female begins to act submissively (National Audubon Society 2014).<ref name="Dumas2000" />
Some displays are performed by the whole flock including up-flights and sky-gazing.<ref name="Dumas2000" /> Up-flights occur after the flock performs an erect posture and then flies up and circles around their territory.<ref name="audubonroseate" /> Sky-gazing occurs when another spoonbill is seen flying and individuals in the flock extend their neck and point their bill to the flying bird.<ref name="Dumas2000" />


During the mating season, roseate spoonbills stay monogamous to their partner and both help to feed and take care of young (TPWD n.d.; National Audubon Society 2014). However, there is no evidence that mates stay together for multiple breeding seasons, suggesting that roseate spoonbills are seasonally monogamous (ARKive n.d.).  
==Habitat==
[[File:Juvenile Roseate Spoonbill ( Ajaia ajaja ) at Lake Woodruff National Wildlife Refuge - Flickr - Andrea Westmoreland.jpg|320px|thumb|right|alt=Juvenile Roseate Spoonbill ( Ajaia ajaja ) feeding|Roseate spoonbill feeding]]
Roseate spoonbills are aquatic wading birds with separate feeding and nesting {{Define|habitat}}s.  


Only males have been seen to use defense mechanisms to defend a wide territory around his nesting site (ARKive n.d.; Prairie Research Institute n.d.). Defense mechanisms may include a threat posture and chasing other spoonbills.<ref name="Dumas2000" /> Males will give up their territory rather than fight if threatened by other species.<ref name="Dumas2000" /> Females will only defend the actual nest.<ref name="Dumas2000" />
===Feeding Habitat===
Their preferred feeding habitat is shallow water with a muddy substrate bottom.<ref name="audubonroseate" /> Since spoonbills use their elongate bill to sift through the mud for food and their ability to lean in is dictated by their height, the water must be shallow for them to successfully forage. The spoonbills’ tarsus, or lower leg, is typically 4.2 to 4.8 inches long, meaning that their preferred water depth is equal to or less than 4.7 inches, on average. When absolutely necessary, spoonbills will occasionally feed in deeper water, where their breast feathers and heads are fully immersed.<ref name="allenaudubon" /><ref name="harrison" /><ref name="lewis" />  


In addition to mating displays, some displays are performed by the whole flock including up-flights and sky-gazing (Prairie Research Institute n.d.).<ref name="Dumas2000" /> Up-flights occur after the flock performs an erect posture and then flies up and circles around their territory (National Audubon Society 2014). Sky-gazing occurs when another spoonbill is seen flying and individuals in the flock extend their neck and point their bill to the flying bird.<ref name="Dumas2000" /> Neither of these group displays are well understood, but have been observed numerous times.
Spoonbills do not seem to be directly affected by salinity and will forage in a variety of salt, brackish, and fresh water habitats.<ref name="Dumas2000" />


==Distribution==
Some specific locations include coastal bays, estuaries, lagoons, seagrass flats, marsh, tidal pools and mosquito control impoundments. One study in Florida found that spoonbills seem to prefer freshwater in some areas, which may be related to a limited ability to deal with hyperosmotic prey.<ref name="britto" />
The roseate spoonbill has an incredibly large distribution across the Americas, with its residential, or non-breeding, range spanning Argentina and Chile northward to the Texas Gulf Coast and Florida (Huey and Dronen, 1981; IUCN, 2001). There has never been a sighting outside of the Americas.<ref name="Dumas2000" /> Many spoonbills are year-round residents of their respective areas, but some do tend to disperse before and after breeding season (IUCN, 2001).<ref name="Dumas2000" />


After breeding season, spoonbills in the U.S. disperse across Florida, Georgia, Louisiana, and Texas, making occasional stops in Alabama and Mississippi for the summer and fall.<ref name="Dumas2000" /> Some spoonbills have even been reported as far north as Nebraska, Pennsylvania, Utah, Illinois, and Wisconsin (Allen, 1942; Lewis, 1983; FNAI, 2001). Although spoonbills are often residents in Florida, Texas, and Louisiana, there are fewer individuals present in the non-breeding season (Lewis, 1983).  
===Nesting Habitat===
[[File:Roseate_spoonbill_couple_McCarthy.jpg|320px|thumb|right|alt=Roseate spoonbill nestlings|Roseate spoonbill nestlings]]
In an attempt to stay far from potential disturbances and predators, Roseate spoonbills primarily nest and roost on islands, islets, or keys, in dense vegetation above ground or standing water.<ref name="lewis" /> Although less preferable, spoonbills will also nest in shrub and forest wetlands on the mainland and occasionally in upland habitats farther inland.<ref name="lewis" />


In the winter, U.S. populations are restricted to the southernmost regions of the Gulf Coast, primarily in south Florida, southwest Louisiana, and coastal Texas.<ref name="Dumas2000" /> Spoonbills are also relatively common in the islands of the Caribbean, except for the Lesser Antilles (FNAI, 2001).
Spoonbills do not require unique nesting habitat and will nest in mixed colonies with egrets, ibises, herons and other wading birds, so long as they are near suitable foraging habitat.<ref name="fnairoseate" />


There is little information on post-breeding dispersal outside of the U.S. and Central America, especially in South America.<ref name="Dumas2000" /> Some think, however, that many roseate spoonbills migrate to Central and South America to avoid the cold climate (TPWD, n.d.; Howell and Webb, 1995).  
Roseate spoonbills construct their nests on shady horizontal branches, five to fifteen feet above ground or water.<ref name="allenaudubon" /><ref name="lewis" /> The highest spoonbill nest recorded measured 98 feet above the ground.<ref name="lewis" />


Although their entire range is poorly documented in South America, spoonbills are known to inhabit some portion of each South American country at some time of year (IUCN, 2001).<ref name="Dumas2000" /> Unlike the spoonbills of the U.S., the spoonbills in South America tend to prefer living and nesting inland around fresh water.<ref name="Dumas2000" />  
No specific vegetation is required, as spoonbills will construct their nests atop any low vegetation, trees, or shrubs with any plant material that is abundant in the nesting location or nearby shoreline.<ref name="white" />


Because little is known about the dispersal dynamics of different populations, some believe the South American populations are distinct from the resident populations in the USA and Central America.<ref name="Dumas2000" />
==Mating==
[[File:Roseate spoonbill nest.jpg|320px|thumb|right|alt=Roseate spoonbill nest.|Roseate spoonbill nest.]]
During courtship, the male and female first interact aggressively toward one another, but then proceed to perch close together with their bills crossed as the female begins to act submissively.<ref name="audubonroseate" />


As for breeding range, in the U.S., the roseate spoonbill breeds along the coasts of Texas, Louisiana, and southern Florida. Outside of the U.S., spoonbills only seem to breed along the coasts of Mexico and Central American countries, although this is not well documented (Howell and Webb, 1995). Little information on breeding range is available in Central and South America.<ref name="Dumas2000" />
Courtship for roseate spoonbills involves ritualized exchanges of nest material such as sticks and twigs from the male to the female to attract her and help her build a deeply cupped nest in vegetation above a water source.<ref name="tpwd" /> Males may head-bob and shake the stick as they deliver nesting materials to a female. Females have been seen to beg for nesting materials with a bowing display.<ref name="Dumas2000" />  


==Habitat==
They typically nest in [[Mangrove|mangroves]] or other trees and shrubs 5 to 15 feet above ground or water. The nest, a bulky platform of sticks with a deep twig, and leaf-lined center is built mainly by the female with material brought by the male.<ref name="matheu" />
Roseate spoonbills are aquatic wading birds with two distinct habitats: 1) feeding habitat, and 2) nesting and roosting habitat.  


Their preferred feeding habitat is shallow water with a muddy substrate bottom (National Audubon Society, 2014). Since spoonbills use their elongate bill to sift through the mud for food and their ability to lean in is dictated by their height, the water must be shallow for them to successfully forage. The spoonbills’ tarsus, or lower leg, is typically 4.2 to 4.8 inches long, meaning that their preferred water depth is equal to or less than 4.7 inches, on average. When absolutely necessary, spoonbills will occasionally feed in deeper water, where their breast feathers and heads are fully immersed (Allen, 1942; Harrison, 1975; Lewis, 1983).  
Clutch size is 2 to 3 eggs, (range 1 to 5). The white eggs are spotted with brown. Eggs are incubated (by both sexes) for 22 to 24 days. Both parents feed the young. Young may leave the nest after 5 to 6 weeks and are capable of strong flight at around 7 to 8 weeks.<ref name="matheu" />


Spoonbills do not seem to be directly affected by salinity and will forage in a variety of hypersaline, marine, brackish, and freshwater habitats (Terres, 1980;FNAI, 2001).<ref name="Dumas2000" /> Some specific locations include coastal bays, estuaries, lagoons, sea grass meadows, marsh, wet prairies, swamps, canals, tidal mudflats, tidal pools, sloughs, lakes, ponds, river drainages, mosquito control impoundments, catfish and crayfish ponds at farms, cattle ponds, and roadside ditches and puddles. (Allen, 1942; Terres, 1980; Britto and Bugoni, 2014; National Audubon Society, 2014).<ref name="Dumas2000" /> One study in Florida found that spoonbills seem to prefer freshwater in some areas, which may be related to a limited ability to deal with hyperosmotic prey (Britto and Bugoni, 2014).
<big>'''Roseate Spoonbill Nesting Facts<ref name="allaboutbirdsroseate" />'''</big>
{| class="wikitable"
| Clutch Size: || 1-5 eggs
|-
| Number of Broods: || 1 brood
|-
| Egg Length: || 2.2-2.8 in
|-
| Incubation Period: || 22 days
|-
| Nestling Period: || 35-42 days
|-
| Egg Description: || Whitish to pale green, evenly covered with brown spots.
|-
| Condition at Hatching: || Pink skinned and covered with white down. Eyed closed and unable to stand.
|}


In attempt to stay far from potential disturbances and predators, spoonbills primarily nest and roost on islands, islets, or keys, in dense vegetation above ground or standing water (Lewis, 1983).<ref name="Dumas2000" /> Although less preferable, spoonbills will also nest in shrub and forest wetlands on the mainland and occasionally in upland habitats farther inland (Lewis, 1983).<ref name="Dumas2000" /> One study from Texas even noted spoonbills nesting directly on the ground (National Audubon Society, 2014).<ref name="Dumas2000" /> Spoonbills do not require unique nesting habitat and are, in fact, known to nest in mixed-species colonies, so long as they are near suitable foraging habitat (FNAI. 2001; National Audubon Society, 2014).
==Threats==
[[File:Roseate Spoonbill Estero Llano SP Mission TX 2018-03-06 10-37-12 (40701327342).jpg|320px|thumb|right|Roseate spoonbill in flight.]]
In the late 1800s, hunting for the feather trade decimated the roseate spoonbill population. The US Migratory Bird Treaty Act of 1918 was enacted, prohibiting the taking of roseate spoonbills, their eggs, and their nests.<ref name="fnairoseate" />


No specific vegetation assemblage is essential, as spoonbills will construct their nests atop any low vegetation, trees, or shrubs with plant material that is abundant in the nesting location or nearby shoreline (White and Cromartie, 1982). Some studies have documented the different tree and shrub species spoonbills frequent for nesting, which include mangroves (Rhizophora spp. and Avicennia spp.), desert hackberry (Celtis pallida), marsh elder (Iva frutescens), bald cypress (Taxodium distichum), elderberry (Sambucus canadensis), sugar hackberry (Celtis laevigata), and willow oak (Quercus phellos) (Allen, 1942; White and Cromartie, 1982; Lewis, 1983).  
Currently, roseate spoonbills are under least concern on the IUCN Red list with a stable population.<ref name="iucn" /> Even though their population is stable, roseate spoonbills are suffering from habitat degradation and loss.<ref name="tpwd" /> Roseate spoonbills feed and nest in coastal marshes, lagoons, mudflats, and mangroves that are being highly altered from coastal development. Tourism in these newly developed areas further degrades the habitat of waterbird species.  


As far as nest placement, spoonbills construct their nests on horizontal branches, five to fifteen feet above ground or water, on average (Allen, 1942; Lewis, 1983; National Audubon Society, 2014). The highest spoonbill nest recorded measured 98 feet above the ground (Lewis, 1983).
Roseate spoonbills have been observed to stay away from high traffic areas, which may affect their migration routes and breeding sites.<ref name="klein" /> Analyzing hydrological processes, nesting distribution, and reproductive success is important when conserving the habitat for the roseate spoonbill.<ref name="bjork94" />


Although spoonbills require different habitat for feeding and nesting, there are no specific habitat requirements for mating. Spoonbills breed throughout their range in a variety of marine, brackish, and freshwater habitats. This includes habitats along the coast in bays/ estuaries, marshes, and beaches, as well as inland in forested swamps, rivers, lakes, and wet prairies (Terres, 1980).<ref name="Dumas2000" />
Along with habitat loss, parasites are also a cause for concern to roseate spoonbill populations. In Southern Florida, 89% of roseate spoonbills examined were found to be infected with parasitic helminths.<ref name="Sepulveda" /> These parasites may come from their diet and lead to pathogens for roseate spoonbills. Texas roseate spoonbills are not infected by similar helminth species as the Florida individuals. One cause for this may be a difference in diet, resulting in different parasites being present.<ref name="Sepulveda" /> In Texas populations, nematode and cestode parasites have been found.<ref name="huey" /> The effects of these parasites is not well known but may lead to eggshell thinning, developmental issues, and an increase in disease.
[[File:Roseate Spoonbill FWS 15049a.jpg|320px|thumb|right|Roseate spoonbill]]
As a result of polluted waters from increased development, the presence of mercury in roseate spoonbill livers has been observed.<ref name="sundlof" /> Increasingly polluted waters affect roseate spoonbills because it increases the concentration of contaminants such as mercury in fish species that constitute a large portion of their diet. Populations that eat larger fish accumulate a greater concentration of mercury in their systems due to biomagnification. Effects of mercury in wading birds include loss of motor skill, an increase in diseases, decreased immune function, embryo mortality, and alterations in behavior. Other toxins that may be of concern to the roseate spoonbill include cadmium, lead, and organochlorides.<ref name="Dumas2000" />


Some of the management practices necessary for maintaining preferable habitat for roseate spoonbills include—maintaining undisturbed/undeveloped areas, riparian habitat, and nature preserves; restricting human disturbance during migration,breeding, and nesting; controlling pollution in aquatic habitats; protecting existing wetlands and restoring degraded wetlands; prohibiting hunting; and providing protection from predators (Allen, 1942).
Predators can threaten the roseate spoonbill population if there is an increase in predator density. Common predators to roseate spoonbills include humans, raccoons, fish crows, great-tailed grackles, and the red imported fire ant.<ref name="drees" /> Many of these predators attack the eggs and nestlings of waterbirds. To decrease the effects of predators on prey populations, monitoring the interaction and population of each species is necessary.


==Management==
Some of these threats may worsen and lead to a susceptible roseate spoonbill population. In order to prevent this, systematic monitoring schemes, conservation sites, buffer zones, and water quality monitoring must continue.<ref name="iucn" />
According to the IUCN, the Roseate Spoonbill conservation status is currently of “least concern,” meaning that it is in no imminent danger of extinction (IUCN, 2001). However, the species should still be protected and subject to a strict management plan. Perhaps the most important conservation problem for this species is the degradation and destruction of coastal foraging and nesting habitat.<ref name="Dumas2000" />  


In the late 1800s, hunting for the feather trade decimated the roseate spoonbill population. Although hunting is not currently an issue, hunting should continue to be prohibited (TPWD, n.d.).<ref name="Dumas2000" /> One major step toward protecting roseate spoonbills was the US Migratory Bird Treaty Act of 1918, which now prohibits the taking of roseate spoonbills, their eggs, and their nests (FNAI, 2001).
==Conservation and Management==
[[File:Juvenile Roseate Spoonbill (4205060854).jpg|320px|thumb|right|Juvenile Roseate spoonbill]]
Today, the roseate spoonbill is protected in the United States by the [https://www.fws.gov/birds/policies-and-regulations/laws-legislations/migratory-bird-treaty-act.php#:~:text=The%20Migratory%20Bird%20Treaty%20Act%20prohibits%20the%20take%20(including%20killing,U.S.%20Fish%20and%20Wildlife%20Service. U.S. Migratory Bird Treaty Act of 1918] and in Florida as a State-designated Threatened species by [https://www.flrules.org/gateway/ChapterHome.asp?Chapter=68A-27 Florida’s Endangered and Threatened Species Rule].<ref name="fwcroseate" />


Another major threat to roseate spoonbills is food availability, which is easily threatened by reduced fresh-water inflow and hypersalinity exceeding physiological tolerance of prey (White and Cromartie, 1982; Sundlof et al., 1994; Lorenz et al., 2009).<ref name="Dumas2000" /> In addition to salinity issues, pesticides and other toxic contaminants such as organochlorides (DDT, DDD, dieldrin) and heavy metals (cadmium, lead), are harmful to both roseate spoonbills and their prey.<ref name="Dumas2000" /> With proper coastal water management, however, these last two threats are manageable.
Perhaps the most important {{Define|conservation}} problem for this species is the degradation and destruction of coastal foraging and nesting habitat.<ref name="Dumas2000" />  


Overall, some of the management practices necessary for maintaining preferable habitat for roseate spoonbills include--maintaining undisturbed/undeveloped areas, riparian habitat, and nature preserves; restricting human disturbance during migration, breeding, and nesting by creating no-access buffer zones; controlling pollution in aquatic habitats; protecting existing wetlands and restoring degraded wetlands; prohibiting hunting; and providing protection from predators like feral dogs and raccoons (Allen, 1942; FNAI, 2001).  
Some of the human activities that put the roseate spoonbill population at risk include: recreational development, channelization of streams, creation of locks and dams, dredging, increasing boat traffic, draining wetlands, applying pesticide on agricultural land, and deforestation.<ref name="Dumas2000" />


Some of the human activities that put the roseate spoonbill population at risk include--recreational development, channelization of streams, creation of locks and dams, dredging, increasing boat traffic, draining wetlands, applying pesticide on agricultural land, and deforestation (Allen, 1942).<ref name="Dumas2000" />
A major threat to roseate spoonbills is food availability, which is easily threatened by reduced freshwater inflow and hypersalinity exceeding the physiological tolerance of prey.<ref name="Dumas2000" />  


For now, the main goal should be the continual protection of the roseate spoonbill’s foraging and nesting habitat to ensure recruitment opportunities in the future (Allen, 1942).<ref name="Dumas2000" /> In order to properly manage the roseate spoonbill population, a few aspects of their biology need to be thoroughly investigated. Some areas of future research should include nesting and breeding ecology, diet and foraging ecology, demographic parameters, population genetics, and behavioral repertoire.<ref name="Dumas2000" />
In addition to salinity issues, pesticides and other toxic contaminants such as organochlorides (DDT, DDD, dieldrin) and heavy metals (cadmium, lead), are harmful to both roseate spoonbills and their prey.<ref name="Dumas2000" /> With proper coastal water management, however, these last two threats are manageable.


==Threats==
Overall, some of the management practices necessary for maintaining preferable habitat for roseate spoonbills include--maintaining undisturbed/undeveloped areas, riparian habitat, and nature preserves; restricting human disturbance during migration, breeding, and nesting by creating no-access buffer zones; controlling pollution in aquatic habitats; protecting existing wetlands and restoring degraded wetlands; prohibiting hunting; and providing protection from predators like feral dogs and raccoons.<ref name="allenaudubon" /><ref name="fnairoseate" />
Currently, roseate spoonbills are under least concern on the IUCN Red list with a stable population (IUCN 2012). However, in the late 1800s, they were greatly threatened.  


Between 1850 and 1890, roseate spoonbills saw their greatest population decrease. These wading birds were hunted for their feathers and meat (ARKive n.d.; Prairie Research Institute n.d.). Their feathers were used for fans and hats, and their meat provided food for fishermen and Indians.  
For now, the main goal should be the continual protection of the roseate spoonbill’s foraging and nesting habitat to ensure recruitment opportunities in the future.<ref name="allenaudubon" /> In order to properly manage the roseate spoonbill population, a few aspects of their biology need to be thoroughly investigated. Some areas of future research should include nesting and breeding ecology, diet and foraging ecology, demographic parameters, population genetics, and behavioral repertoire.<ref name="Dumas2000" />
</div>
<div class="irlvideo">
==Video==
{{#evl:4bUNlC7N88Y|Roseate Spoonbills in Florida|1|player=youtube}}


Along with being hunted, their habitat was also destroyed by civilization and oil development (Prairie Research Institute n.d.). Sharing a habitat with hunted egrets was another cause for their population decrease because breeding colonies would be indirectly affected by hunters (ARKive n.d.).
{{#evl:GR-OZixT7kM|Roseate Spoonbill Feeding Nestlings|2|player=youtube}}


Even though their population is currently stable, roseate spoonbills are suffering from habitat degradation and loss (Cornell Lab of Ornithology 2015; TPWD n.d.; Smithsonian n.d.).
{{#evl:i5khCf-Rwq0|Spoonbills an indicator of health for Florida Bay|3|player=youtube}}


Roseate spoonbills feed and nest in coastal marshes, lagoons, mudflats, and mangroves that are being highly altered from coastal development (Cornell Lab of Ornithology 2015; Smithsonian n.d.). Tourism in these newly developed areas further degrades the habitat of waterbird species. Roseate spoonbills have been observed to stay away from high traffic areas, which may affect their migration routes and breeding sites (Klein et al. 1995). Analyzing hydrological processes, nesting distribution, and reproductive success is important when conserving the habitat for the roseate spoonbill (Bjork and Powell 1994).
<evlplayer w="320" id="youtube">
 
Please select a Roseate spoonbill video to view.
Along with habitat loss, parasitic helminths are also a cause for concern to roseate spoonbill populations. In Southern Florida, 89% of roseate spoonbills examined were found to be infected with parasitic helminths (Sepulveda et al. 1994). These parasites may come from the diet of roseate spoonbill populations and lead to pathogens for roseate spoonbills. Texas roseate spoonbills are not infected by similar helminth species as the Florida individuals. One cause for this may be a difference in diet, resulting in different parasites being present (Sepulveda et al. 1994). In Texas populations, nematode and cestode parasites have been found (Huey and Dronen 1981). Effects of these parasites is not well known but may lead to eggshell thinning, developmental issues, and increase in disease (Smithsonian n.d.).
[[File:Roseate Spoonbill (43511198055).jpg|320px|frameless|left|link=]]
 
</evlplayer>
As a result of polluted waters from increased development, the presence of mercury in roseate spoonbill livers has been observed (Sundlof et al. 1994). Increasingly polluted waters affect roseate spoonbills because it increases the concentration of contaminants such as mercury in fish species that constitute a large portion of their diet. Populations that eat larger fish accumulate a greater concentration of mercury in their systems due to biomagnification. Effects of mercury in wading birds include loss of motor skill, increase in diseases, decreased immune function, embryo mortality, and alterations in behavior (Audubon Society of the Everglades). Other toxins that may be of concern to the roseate spoonbill include cadmium, lead, and organochlorides.<ref name="Dumas2000" />
</div>
 
<div class="irlcontentbottom noprint">
Predators can threaten the roseate spoonbill population if there is an increase in predator density. Common predators to roseate spoonbills include humans, raccoons, fish crows, great-tailed grackles, and the red imported fire ant (Solenopsis invicta) (Prairie Research Institute n.d.; Drees 1994). Many of these predators attack the eggs and nestlings of waterbirds. To decrease the effects of predators on prey populations, monitoring the interaction and population of each species is necessary.
==See Also==
Some of these threats may worsen and lead to a susceptible roseate spoonbill population. In order to prevent this, systematic monitoring schemes, conservation sites, buffer zones, and water quality monitoring must continue (Florida Natural Areas Inventory 2001; IUCN 2012)
[[Roseate Spoonbill Pictures|Roseate Spoonbill Photo Gallery]]


<div class="irlcontentmiddle">
==Documents==
==Images==
* [https://www.fnai.org/FieldGuide/pdf/Ajaia_ajaja.pdf Florida Natural Areas Inventory - Roseate spoonbill (PDF, 2pp, 48KB)]
[[File:Roseate_Spoonbill_balancing_KSC99pp0364.jpg|320px|thumb|left|Roseate Spoonbill in Merritt Island National Wildlife Refuge]]
* [https://myfwc.com/media/2151/wading-birds-species-action-plan-final-draft.pdf FWC - A Species Action Plan for Six Imperiled Wading Birds (PDF)]
[[File:Roseate spoonbill (Ajaia ajaja).JPG|320px|thumb|left|Roseate spoonbill (Platalea ajaja) wading in the Indian River Lagoon.]]
* [http://www.texasthestateofwater.org/screening/pdf_docs/fact_sheets/roseate_spoonbill.pdf Roseate Spoonbill Factsheet (PDF)]
[[File:Roseate Spoonbill 741903422.jpg|320px|thumb|right|Roseate spoonbill in flight.]]
* [https://www.researchgate.net/publication/222430492_Roseate_spoonbill_reproduction_as_an_indicator_for_restoration_of_the_Everglades_and_the_Everglades_estuaries Roseate spoonbill reproduction as an indicator for restoration of the Everglades and the Everglades estuaries. (PDF)]


[[File:Merritt_island-0480.jpg|320px|thumb|left|Roseate spoonbill feeding at Merritt Island National Wildlife Refuge.]]
==Weblinks==
[[File:Roseate Spoonbill - Myakka River State Park.jpg|320px|thumb|right|Roseate Spoonbill (Platalea ajaja) in the estuary]]
* [https://eol.org/pages/45509056 Encyclopedia of Life - Roseate spoonbill]
</div>
* [https://myfwc.com/wildlifehabitats/profiles/birds/waterbirds/roseate-spoonbill/ Florida Wildlife Conservation - Roseate spoonbill]
* [https://www.fws.gov/refuge/JN_Ding_Darling/wildlife_and_habitat/roseate_spoonbill.html FWS Darling National Wildlife Refuge - Roseate spoonbill]
* [https://nationalzoo.si.edu/animals/roseate-spoonbill Smithsonian National Zoo - Roseate spoonbill]
* [https://www.allaboutbirds.org/guide/Roseate_Spoonbill All About Birds - Roseate spoonbill]
* [https://www.nps.gov/bicy/learn/nature/roseate-spoonbill.htm National Park Service - Roseate spoonbill]
* [https://tpwd.texas.gov/huntwild/wild/species/spoonbill/ Texas Parks and Wildlife - Roseate spoonbill]
* [https://www.tampabay.com/environment/for-one-rare-bird-flight-from-south-floridas-changing-climate-sparks-a-surprising-revival-20190702/ Roseate spoonbill in Tampa Bay]
* [https://fl.audubon.org/news/audubon-studies-roseate-spoonbill-track-population-rebound Roseate Spoonbill Population Rebound]
* [https://www.iucnredlist.org/species/22697574/93621961 IUCN Red List of Threatened Secies - Roseate spoonbill]
* [https://www.fws.gov/birds/policies-and-regulations/laws-legislations/migratory-bird-treaty-act.php#:~:text=The%20Migratory%20Bird%20Treaty%20Act%20prohibits%20the%20take%20(including%20killing,U.S.%20Fish%20and%20Wildlife%20Service. U.S. Migratory Bird Treaty Act]
* [https://www.flrules.org/gateway/ChapterHome.asp?Chapter=68A-27  Florida Rule 68A-27 - Endangered or Threatened Species]


<div class="irlcontentbottom">
==References==
==References==
<ref name="Dumas2000">Dumas, J. V. 2000. Roseate spoonbill. The Birds of North America. Cornell Lab of Ornithology.</ref>
<div class="mw-collapsible mw-collapsed" style="float:left">
<references>
<ref name="fwcroseate">[https://myfwc.com/wildlifehabitats/profiles/birds/waterbirds/roseate-spoonbill/ FWC Roseate spoonbill Profile]</ref>


National Audubon Society. 2014. Roseate spoonbill (Platalea ajaja). Field Guide.
<ref name="tpwd">[https://tpwd.texas.gov/huntwild/wild/species/spoonbill/ Texas Parks and Widlife - Roseate spoonbill]</ref>


Rojas, L.M., R. McNeil, T. Cabana, and P. Lachapelle. 1999. Behavioral, morphological and physiological correlates of diurnal and nocturnal vision in selected wading bird species. Brain, Behavior and Evolution 53:227-242.
<ref name="natzooroseate">[https://nationalzoo.si.edu/animals/roseate-spoonbill National Zoo - Roseate spoonbill]</ref>


Roseate spoonbill (Platalea ajaja). ARKive. 10 April 2016.
<ref name="fwsdarlingroseate">[https://www.fws.gov/refuge/JN_Ding_Darling/wildlife_and_habitat/roseate_spoonbill.html Darling National Wildlife Refuge - Roseate spoonbill]</ref>


Roseate spoonbill (Platalea ajaja). Illinois Natural History Survey. Prairie Research Institute.
<ref name="allaboutbirdsroseate">.[https://www.allaboutbirds.org/guide/Roseate_Spoonbill/lifehistory All About Birds - Roseate spoonbill]</ref>


Roseate spoonbill. Smithsonian National Zoological Park. 10 April 2016.
<ref name="Dumas2000">Dumas, J. V. 2000. Roseate spoonbill. The Birds of North America. Cornell Lab of Ornithology.</ref>
 
Allen, R. P. 1942. The Roseate Spoonbill. National Audubon Society.
 
BirdLife International. 2012. Platalea ajaja (Roseate Spoonbill). The IUCN Red List of Threatened Species. IUCN.


Florida Natural Areas Inventory (FNAI). 2001. Roseate spoonbill (Platalea ajaja). Field Guide to the Rare Animals of Florida.
<ref name="rojas">Rojas, L.M., R. McNeil, T. Cabana, and P. Lachapelle. 1999. Behavioral, morphological and physiological correlates of diurnal and nocturnal vision in selected wading bird species. Brain, Behavior and Evolution 53:227-242.</ref>


Howell, S. N. G. and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press.
<ref name="audubonroseate">National Audubon Society. 2014. Roseate spoonbill (Platalea ajaja). Field Guide.</ref>


Huey, R., and N. Dronen. 1981. Nematode and Cestode Parasites from the Roseate Spoonbill, Ajaia ajaja, including Paradilepis diminuta sp. n. (Cestoda: Dilepididae). The Journal of Parasitology 67:721–723. doi:10.2307/3280450
<ref name="arkive">Roseate spoonbill (Platalea ajaja). ARKive. 10 April 2016.</ref>


Lewis, J.C. 1983. Habitat suitability index models: roseate spoonbill. U.S. Department of the Interior Fish and Wildlife Service.
<ref name="howell">Howell, S. N. G. and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press.</ref>


Texas Parks & Wildlife (TPWD). N.d. Roseate Spoonbill (Platalea ajaja). Wildlife Fact Sheets.
<ref name="huey">Huey, R., and N. Dronen. 1981. Nematode and Cestode Parasites from the Roseate Spoonbill, Ajaia ajaja, including Paradilepis diminuta sp. n. (Cestoda: Dilepididae). The Journal of Parasitology 67:721–723. doi:10.2307/3280450</ref>


Britto, V., and L. Bugoni. 2014. The contrasting feeding ecology of great egrets and roseate spoonbills in limnetic and estuarine colonies. Hydrobiologia 744:187–210. doi: 10.1007/s10750-014-2076-1.
<ref name="sundlof">Sundlof, S., M. Spalding, J. Wentworth, and C. Steible. 1994. Mercury in livers of wading birds (ciconiiformes) in southern Florida. Archives of Environmental Contamination and Toxicology 27:299-305. doi:10.1007/bf00213163</ref>


Harrison, H. H. 1975. Field guide to birds' nests. Houghton-Mifflin, Boston.
<ref name="allenaudubon">Allen, R. P. 1942. The Roseate Spoonbill. National Audubon Society.</ref>


Lewis, J.C. 1983. Habitat suitability index models: roseate spoonbill. U.S. Department of the Interior Fish and Wildlife Service.
<ref name="fnairoseate">Florida Natural Areas Inventory (FNAI). 2001. Roseate spoonbill (Platalea ajaja). Field Guide to the Rare Animals of Florida.</ref>


Terres, J. K. 1980. The Audubon Society: Encyclopedia of North American Birds. Knopf, New York.
<ref name="harrison">Harrison, H. H. 1975. Field guide to birds' nests. Houghton-Mifflin, Boston.</ref>


White, C. Mitchell, and E. Cromartie. 1982. Nesting Ecology of Roseate Spoonbills at Nueces Bay, Texas. The American Ornithologists' Union 99:275–284.
<ref name="lewis">Lewis, J.C. 1983. Habitat suitability index models: roseate spoonbill. U.S. Department of the Interior Fish and Wildlife Service.</ref>


Lorenz, J. J., B. Langan-Mulrooney, P. E. Frezza, R. G. Harvey, and F. J. Mazzotti. 2009. Roseate spoonbill reproduction as an indicator for restoration of the Everglades and the Everglades estuaries. Ecological Indicators 9:96–107. doi:10.1016/j.ecolind.2008.10.008
<ref name="britto">Britto, V., and L. Bugoni. 2014. The contrasting feeding ecology of great egrets and roseate spoonbills in limnetic and estuarine colonies. Hydrobiologia 744:187–210. doi: 10.1007/s10750-014-2076-1.</ref>


Sundlof, S., M. Spalding, J. Wentworth, and C. Steible. 1994. Mercury in livers of wading birds (ciconiiformes) in southern Florida. Archives of Environmental Contamination and Toxicology 27:299-305. doi:10.1007/bf00213163
<ref name="klein">Klein, M.L., S.R. Humphrey, and H.F. Percival. 1995. Effects of ecotourism on distribution of waterbirds in wildlife refuge. Conservation Biology 9:1454-1465.</ref>


Bjork, R.D. and G.V.N. Powell. 1994. Relationships between hydrologic conditions and quality and quantity of foraging habitat for roseate spoonbills and other wading birds in the C-111 Basin. Final Report to the South Florida Research Center. National Audubon Society.
<ref name="Sepulveda">Sepulveda, M.S., M.G. Spalding, J.M. Kinsella, R.D. Bjork, and G.S. McLaughlin. 1994. Helminths of the Roseate spoonbill, Ajaia ajaja, in Southern Florida. Journal of the Helmninthological Society of Washington 61:179-189.</ref>


Drees, B.M. 1994 Red imported fire ant predation on nestlings of colonial waterbirds. Soutwestern Entomologist 19: 355-359.
<ref name="iucn">[https://www.iucnredlist.org IUCN Red List of Threatened Species], BirdLife International. 2012. Platalea ajaja (Roseate Spoonbill). The IUCN Red List of Threatened Species. IUCN.</ref>


Klein, M.L., S.R. Humphrey, and H.F. Percival. 1995. Effects of ecotourism on distribution of waterbirds in wildlife refuge. Conservation Biology 9:1454-1465.
<ref name="white">White, C. Mitchell, and E. Cromartie. 1982. Nesting Ecology of Roseate Spoonbills at Nueces Bay, Texas. The American Ornithologists' Union 99:275–284.</ref>


Mercury. Audubon Society of the Everglades. 10 April 2016.
<ref name="drees">Drees, B.M. 1994 Red imported fire ant predation on nestlings of colonial waterbirds. Soutwestern Entomologist 19: 355-359.</ref>


Roseate spoonbill. The Cornell Lab of Ornithology. 2015.
<ref name="bjork94">Bjork, R.D. and G.V.N. Powell. 1994. Relationships between hydrologic conditions and quality and quantity of foraging habitat for roseate spoonbills and other wading birds in the C-111 Basin. Final Report to the South Florida Research Center. National Audubon Society.</ref>


Roseate Spoonbill (Platalea ajaja). Texas Parks & Wildlife. 10 April 2016.
<ref name="matheu">Matheu, E. & del Hoyo, J. 1992. Family Threskiornithidae (ibises and spoonbills). In del Hoyo, J., Elliot, A. and Sargatal, J. (eds.) Handbook of the Birds of the World, 472–506. Lynx Edicions, Barcelona. [Google Scholar]</ref>
 
</references>
Sepulveda, M.S., M.G. Spalding, J.M. Kinsella, R.D. Bjork, and G.S. McLaughlin. 1994. Helminths of the Roseate spoonbill, Ajaia ajaja, in Southern Florida. Journal of the Helmninthological Society of Washington 61:179-189.
</div>
</div>
 
{{IRL footer estuary|cat=Biota}}
{{IRL footer biota}}
</div>
</div>
[[Category:Land Animals]]
[[Category:Land Animals]]
[[Category:Endangered Species]]

Latest revision as of 09:03, December 1, 2021

Indian River Lagoon Encyclopedia
Indian River Lagoon Encyclopedia - Biota
Biota
Roseate Spoonbill (Platalea ajaja)
Roseate spoonbill
Platalea ajaja
Status: State Threatened

The Roseate spoonbill (Platalea ajaja) is a medium-sized, pink-bodied, wading bird with a flat spatula-shaped bill. They are found in the southeastern United States and West Indies through Mexico and Central America to South America. The Roseate spoonbill is the only spoonbill native to the Western Hemisphere and the only pink bird that breeds in Florida. Spoonbills can be seen within the Indian River Lagoon National Estuary at the Merritt Island National Wildlife Refuge in Titusville, Florida.

Roseate spoonbills feed by sweeping their spoon-shaped bills side to side, often sifting through mud as they walk through shallow water. Their diet includes small fishes and aquatic invertebrates, as well as some plant material. They are found in coastal marshes, lagoons, mudflats, and mangrove keys, foraging in salt, fresh and brackish water. Flocks typically include fewer than half a dozen individuals.

Spoonbills reach maturity at approximately 16 weeks. Females typically lay two to five brown-speckled white eggs, which hatch after about 24 days. In about eight weeks, the young roseate spoonbills are ready to fly.[1] Spoonbills can live up to 15 years in human care and an estimated 10 years in the wild.[2]

Appearance

Roseate spoonbills have pink wings and underparts (with some red on the tops of the wings) with a white neck and back, and pinkish legs and feet.[3] They can reach a length of 30-40 inches with a wingspan of 50-53 inches[3] and weigh up to 4 pounds.[4]

The pink coloration of spoonbill feathers is caused by an abundance of carotenoids, or algae pigments, present in the food the birds eat. As the spoonbill ages, the carotenoids accumulate from all of the aquatic animals it has eaten and the pink coloration becomes darker.[4] No other Florida species is similar. The roseate spoonbill is the only spoonbill native to the Western Hemisphere and is the only pink bird that breeds in Florida.[3]

Distribution

Roseate spoonbill (Platalea ajaja) in flight
Spoonbill in flight

The roseate spoonbill has an incredibly large distribution across the Americas, with its residential, or non-breeding, range spanning Argentina and Chile northward to the Texas Gulf Coast and Florida.[5] There has never been a sighting outside of the Americas.[6]

In the winter, U.S. populations are restricted to the southernmost regions of the Gulf Coast, primarily in south Florida, southwest Louisiana, and coastal Texas.[6] In Florida, the species is found in Florida Bay, Tampa Bay, and Brevard County.[3]

Although their range is poorly documented in South America, spoonbills are known to inhabit some portion of each South American country at some time of year.[7] Unlike the spoonbills of the U.S., the spoonbills in South America tend to prefer living and nesting inland around freshwater.[6] Some believe the South American populations are distinct from the resident populations in the USA and Central America.[6]

As for breeding range, in the U.S., the roseate spoonbill breeds along the coasts of Texas, Louisiana, and southern Florida. Outside of the U.S., spoonbills only seem to breed along the coasts of Mexico and Central American countries.[8] Little information on the spoonbills breeding range is available in Central and South America.[6]

Behavior

Roseate Spoonbill (Platalea ajaja)
Roseate Spoonbill (Platalea ajaja)

Roseate spoonbills forage using tacto-location to locate food while wading through shallow, muddy waters. In the early mornings and evenings, they slowly walk with their bill partially submerged, swinging it side to side, to sift out food from mud and water. The mandible contains nerve endings that snap the jaw shut as it contacts prey.[6]

Catching prey by feeling, roseate spoonbills are able to forage without light, and thus their eye structure is not highly developed.[9] Roseate spoonbills eat smaller prey. This includes fish such as minnows and killifish; crustaceans such as shrimp, crayfish, and crabs; aquatic insects; mollusks; slugs; and plant material such as roots and stems.[10] If needed, roseate spoonbills may beat prey against a hard surface to aid in digestion .[11]

Roseate spoonbills preen using their bill to nibble and run down the length of each feather, starting with their lower neck and down to their breast and abdomen. They clean their bill by dipping the tip in the water and then shaking their head to dry the bill.[6]

Sleeping occurs communally with the roseate spoonbills standing on one leg, with their head turned backward underneath feathers in their upper back.[6]

Members within a flock have been seen having a sham battle. This interaction does not harm either fighter, and it is unknown why this behavior is done. In the sham battle, two birds fly at each other, and may rise about a meter off the ground as they beat their wings.[6]

When faced with a threat, roseate spoonbills alert the colony by standing tall with their neck outstretched and head held high. An alarm call may come in addition to this stance to call further attention to the threat. When fighting a threat, they hold the axis of their body parallel to the ground with their head lowered, neck outstretched, and wings raised above their body. Striking with their bill may result if the threat is intensified. One threat that causes this kind of behavior includes territorial defense against an encroaching member of an outside flock.[6]

Only males have been seen to use defense mechanisms to defend a wide territory around his nesting site.[11] Defense mechanisms may include a threat posture and chasing other spoonbills. Males will give up their territory rather than fight if threatened by other species. Females will only defend the actual nest.[6]

Some displays are performed by the whole flock including up-flights and sky-gazing.[6] Up-flights occur after the flock performs an erect posture and then flies up and circles around their territory.[10] Sky-gazing occurs when another spoonbill is seen flying and individuals in the flock extend their neck and point their bill to the flying bird.[6]

Habitat

Juvenile Roseate Spoonbill ( Ajaia ajaja ) feeding
Roseate spoonbill feeding

Roseate spoonbills are aquatic wading birds with separate feeding and nesting habitats.

Feeding Habitat

Their preferred feeding habitat is shallow water with a muddy substrate bottom.[10] Since spoonbills use their elongate bill to sift through the mud for food and their ability to lean in is dictated by their height, the water must be shallow for them to successfully forage. The spoonbills’ tarsus, or lower leg, is typically 4.2 to 4.8 inches long, meaning that their preferred water depth is equal to or less than 4.7 inches, on average. When absolutely necessary, spoonbills will occasionally feed in deeper water, where their breast feathers and heads are fully immersed.[12][13][14]

Spoonbills do not seem to be directly affected by salinity and will forage in a variety of salt, brackish, and fresh water habitats.[6]

Some specific locations include coastal bays, estuaries, lagoons, seagrass flats, marsh, tidal pools and mosquito control impoundments. One study in Florida found that spoonbills seem to prefer freshwater in some areas, which may be related to a limited ability to deal with hyperosmotic prey.[15]

Nesting Habitat

Roseate spoonbill nestlings
Roseate spoonbill nestlings

In an attempt to stay far from potential disturbances and predators, Roseate spoonbills primarily nest and roost on islands, islets, or keys, in dense vegetation above ground or standing water.[14] Although less preferable, spoonbills will also nest in shrub and forest wetlands on the mainland and occasionally in upland habitats farther inland.[14]

Spoonbills do not require unique nesting habitat and will nest in mixed colonies with egrets, ibises, herons and other wading birds, so long as they are near suitable foraging habitat.[16]

Roseate spoonbills construct their nests on shady horizontal branches, five to fifteen feet above ground or water.[12][14] The highest spoonbill nest recorded measured 98 feet above the ground.[14]

No specific vegetation is required, as spoonbills will construct their nests atop any low vegetation, trees, or shrubs with any plant material that is abundant in the nesting location or nearby shoreline.[17]

Mating

Roseate spoonbill nest.
Roseate spoonbill nest.

During courtship, the male and female first interact aggressively toward one another, but then proceed to perch close together with their bills crossed as the female begins to act submissively.[10]

Courtship for roseate spoonbills involves ritualized exchanges of nest material such as sticks and twigs from the male to the female to attract her and help her build a deeply cupped nest in vegetation above a water source.[1] Males may head-bob and shake the stick as they deliver nesting materials to a female. Females have been seen to beg for nesting materials with a bowing display.[6]

They typically nest in mangroves or other trees and shrubs 5 to 15 feet above ground or water. The nest, a bulky platform of sticks with a deep twig, and leaf-lined center is built mainly by the female with material brought by the male.[18]

Clutch size is 2 to 3 eggs, (range 1 to 5). The white eggs are spotted with brown. Eggs are incubated (by both sexes) for 22 to 24 days. Both parents feed the young. Young may leave the nest after 5 to 6 weeks and are capable of strong flight at around 7 to 8 weeks.[18]

Roseate Spoonbill Nesting Facts[19]

Clutch Size: 1-5 eggs
Number of Broods: 1 brood
Egg Length: 2.2-2.8 in
Incubation Period: 22 days
Nestling Period: 35-42 days
Egg Description: Whitish to pale green, evenly covered with brown spots.
Condition at Hatching: Pink skinned and covered with white down. Eyed closed and unable to stand.

Threats

Roseate spoonbill in flight.

In the late 1800s, hunting for the feather trade decimated the roseate spoonbill population. The US Migratory Bird Treaty Act of 1918 was enacted, prohibiting the taking of roseate spoonbills, their eggs, and their nests.[16]

Currently, roseate spoonbills are under least concern on the IUCN Red list with a stable population.[7] Even though their population is stable, roseate spoonbills are suffering from habitat degradation and loss.[1] Roseate spoonbills feed and nest in coastal marshes, lagoons, mudflats, and mangroves that are being highly altered from coastal development. Tourism in these newly developed areas further degrades the habitat of waterbird species.

Roseate spoonbills have been observed to stay away from high traffic areas, which may affect their migration routes and breeding sites.[20] Analyzing hydrological processes, nesting distribution, and reproductive success is important when conserving the habitat for the roseate spoonbill.[21]

Along with habitat loss, parasites are also a cause for concern to roseate spoonbill populations. In Southern Florida, 89% of roseate spoonbills examined were found to be infected with parasitic helminths.[22] These parasites may come from their diet and lead to pathogens for roseate spoonbills. Texas roseate spoonbills are not infected by similar helminth species as the Florida individuals. One cause for this may be a difference in diet, resulting in different parasites being present.[22] In Texas populations, nematode and cestode parasites have been found.[5] The effects of these parasites is not well known but may lead to eggshell thinning, developmental issues, and an increase in disease.

Roseate spoonbill

As a result of polluted waters from increased development, the presence of mercury in roseate spoonbill livers has been observed.[23] Increasingly polluted waters affect roseate spoonbills because it increases the concentration of contaminants such as mercury in fish species that constitute a large portion of their diet. Populations that eat larger fish accumulate a greater concentration of mercury in their systems due to biomagnification. Effects of mercury in wading birds include loss of motor skill, an increase in diseases, decreased immune function, embryo mortality, and alterations in behavior. Other toxins that may be of concern to the roseate spoonbill include cadmium, lead, and organochlorides.[6]

Predators can threaten the roseate spoonbill population if there is an increase in predator density. Common predators to roseate spoonbills include humans, raccoons, fish crows, great-tailed grackles, and the red imported fire ant.[24] Many of these predators attack the eggs and nestlings of waterbirds. To decrease the effects of predators on prey populations, monitoring the interaction and population of each species is necessary.

Some of these threats may worsen and lead to a susceptible roseate spoonbill population. In order to prevent this, systematic monitoring schemes, conservation sites, buffer zones, and water quality monitoring must continue.[7]

Conservation and Management

Juvenile Roseate spoonbill

Today, the roseate spoonbill is protected in the United States by the U.S. Migratory Bird Treaty Act of 1918 and in Florida as a State-designated Threatened species by Florida’s Endangered and Threatened Species Rule.[3]

Perhaps the most important conservation problem for this species is the degradation and destruction of coastal foraging and nesting habitat.[6]

Some of the human activities that put the roseate spoonbill population at risk include: recreational development, channelization of streams, creation of locks and dams, dredging, increasing boat traffic, draining wetlands, applying pesticide on agricultural land, and deforestation.[6]

A major threat to roseate spoonbills is food availability, which is easily threatened by reduced freshwater inflow and hypersalinity exceeding the physiological tolerance of prey.[6]

In addition to salinity issues, pesticides and other toxic contaminants such as organochlorides (DDT, DDD, dieldrin) and heavy metals (cadmium, lead), are harmful to both roseate spoonbills and their prey.[6] With proper coastal water management, however, these last two threats are manageable.

Overall, some of the management practices necessary for maintaining preferable habitat for roseate spoonbills include--maintaining undisturbed/undeveloped areas, riparian habitat, and nature preserves; restricting human disturbance during migration, breeding, and nesting by creating no-access buffer zones; controlling pollution in aquatic habitats; protecting existing wetlands and restoring degraded wetlands; prohibiting hunting; and providing protection from predators like feral dogs and raccoons.[12][16]

For now, the main goal should be the continual protection of the roseate spoonbill’s foraging and nesting habitat to ensure recruitment opportunities in the future.[12] In order to properly manage the roseate spoonbill population, a few aspects of their biology need to be thoroughly investigated. Some areas of future research should include nesting and breeding ecology, diet and foraging ecology, demographic parameters, population genetics, and behavioral repertoire.[6]

Video

Roseate Spoonbills in Florida

Roseate Spoonbill Feeding Nestlings

Spoonbills an indicator of health for Florida Bay

Please select a Roseate spoonbill video to view.

Roseate Spoonbill (43511198055).jpg

See Also

Roseate Spoonbill Photo Gallery

Documents

Weblinks

References

  1. ↑ 1.0 1.1 1.2 Texas Parks and Widlife - Roseate spoonbill
  2. ↑ National Zoo - Roseate spoonbill
  3. ↑ 3.0 3.1 3.2 3.3 3.4 FWC Roseate spoonbill Profile
  4. ↑ 4.0 4.1 Darling National Wildlife Refuge - Roseate spoonbill
  5. ↑ 5.0 5.1 Huey, R., and N. Dronen. 1981. Nematode and Cestode Parasites from the Roseate Spoonbill, Ajaia ajaja, including Paradilepis diminuta sp. n. (Cestoda: Dilepididae). The Journal of Parasitology 67:721–723. doi:10.2307/3280450
  6. ↑ 6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 6.11 6.12 6.13 6.14 6.15 6.16 6.17 6.18 6.19 6.20 Dumas, J. V. 2000. Roseate spoonbill. The Birds of North America. Cornell Lab of Ornithology.
  7. ↑ 7.0 7.1 7.2 IUCN Red List of Threatened Species, BirdLife International. 2012. Platalea ajaja (Roseate Spoonbill). The IUCN Red List of Threatened Species. IUCN.
  8. ↑ Howell, S. N. G. and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press.
  9. ↑ Rojas, L.M., R. McNeil, T. Cabana, and P. Lachapelle. 1999. Behavioral, morphological and physiological correlates of diurnal and nocturnal vision in selected wading bird species. Brain, Behavior and Evolution 53:227-242.
  10. ↑ 10.0 10.1 10.2 10.3 National Audubon Society. 2014. Roseate spoonbill (Platalea ajaja). Field Guide.
  11. ↑ 11.0 11.1 Roseate spoonbill (Platalea ajaja). ARKive. 10 April 2016.
  12. ↑ 12.0 12.1 12.2 12.3 Allen, R. P. 1942. The Roseate Spoonbill. National Audubon Society.
  13. ↑ Harrison, H. H. 1975. Field guide to birds' nests. Houghton-Mifflin, Boston.
  14. ↑ 14.0 14.1 14.2 14.3 14.4 Lewis, J.C. 1983. Habitat suitability index models: roseate spoonbill. U.S. Department of the Interior Fish and Wildlife Service.
  15. ↑ Britto, V., and L. Bugoni. 2014. The contrasting feeding ecology of great egrets and roseate spoonbills in limnetic and estuarine colonies. Hydrobiologia 744:187–210. doi: 10.1007/s10750-014-2076-1.
  16. ↑ 16.0 16.1 16.2 Florida Natural Areas Inventory (FNAI). 2001. Roseate spoonbill (Platalea ajaja). Field Guide to the Rare Animals of Florida.
  17. ↑ White, C. Mitchell, and E. Cromartie. 1982. Nesting Ecology of Roseate Spoonbills at Nueces Bay, Texas. The American Ornithologists' Union 99:275–284.
  18. ↑ 18.0 18.1 Matheu, E. & del Hoyo, J. 1992. Family Threskiornithidae (ibises and spoonbills). In del Hoyo, J., Elliot, A. and Sargatal, J. (eds.) Handbook of the Birds of the World, 472–506. Lynx Edicions, Barcelona. [Google Scholar]
  19. ↑ .All About Birds - Roseate spoonbill
  20. ↑ Klein, M.L., S.R. Humphrey, and H.F. Percival. 1995. Effects of ecotourism on distribution of waterbirds in wildlife refuge. Conservation Biology 9:1454-1465.
  21. ↑ Bjork, R.D. and G.V.N. Powell. 1994. Relationships between hydrologic conditions and quality and quantity of foraging habitat for roseate spoonbills and other wading birds in the C-111 Basin. Final Report to the South Florida Research Center. National Audubon Society.
  22. ↑ 22.0 22.1 Sepulveda, M.S., M.G. Spalding, J.M. Kinsella, R.D. Bjork, and G.S. McLaughlin. 1994. Helminths of the Roseate spoonbill, Ajaia ajaja, in Southern Florida. Journal of the Helmninthological Society of Washington 61:179-189.
  23. ↑ Sundlof, S., M. Spalding, J. Wentworth, and C. Steible. 1994. Mercury in livers of wading birds (ciconiiformes) in southern Florida. Archives of Environmental Contamination and Toxicology 27:299-305. doi:10.1007/bf00213163
  24. ↑ Drees, B.M. 1994 Red imported fire ant predation on nestlings of colonial waterbirds. Soutwestern Entomologist 19: 355-359.
Indian River Lagoon Encyclopedia Article - Roseate spoonbill
Home> Library> Encyclopedia> Biota
Permalink: https://indianriverlagoonnews.org/guide/index.php/Roseate_spoonbill
Retrieved from "https://indianriverlagoonnews.org/guide/index.php?title=Roseate_spoonbill&oldid=22709"