DOCSLIB.ORG

Wet & Wild May: Great Blue Heron

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Wet & Wild May: Great Blue Heron Wet & Wild May: Great Blue Heron With more than 75 acres of open water, birds live along the river, lakes, and streams at Duke Farms are truly “lucky ducks”. One of the most majestic of all the water birds encountered on the property is the great blue heron. This long-legged wader with blue-gray plumage can often be spotted standing motionless in the shallows as it scans the water’s edge for fish, snakes, and frogs. They can pose like statues for what seems an eternity, but when a meal wanders near, the great blue heron stalks and strikes like a stealth bomber. Thanks to specialized neck vertebrae they can snatch an unsuspecting creature with lightning speed. The great blue heron is one of our tallest birds. It stands between 4 and 5 feet with a 6-foot wingspan, but only weighs about 6 pounds! It has long gray legs, a thin neck that it can curl into an s-shape, and an orange pointy bill that it wields like a sword to catch its prey. When it flies, the heron pulls its neck into a tight s-shape close to its body while its long legs dangle out behind. It’s understandable that pterodactyl comes to mind when the bird flies overhead. Great blues live in both freshwater and saltwater habitats and usually forage alone. They are not picky eaters and will just as soon dine on small rodents, crustaceans, and insects as much as fish. Herons swallow their prey whole and can digest almost all parts of the creatures that they swallow, including the bones. In some cases, they will cast out indigestible pellets like owls do. The sight of a heron struggling to swallow a whole writhing snake is awfully reminiscent of a sword swallower in a circus. Only the bird doesn’t have hands to assist with the struggle. It snatches the snake with its long beak and whips the snake down its throat! Herons are found throughout most of the United States and coastal Mexico year-round. They also breed in Canada in the summer and winter all the way through central America. Most of the year great blue herons are spotted by themselves, but not so during the breeding season. Great blues nest in colonies called heronries. Sometimes a colony consists of just a few families but in some places more than 500 individual nests make up the colony! The birds mostly nest in trees with multiple nests in each tree. In wetland habitats where trees are scarce, they have been known to nest on the ground, in shrubs, and even on structures and artificial nest platforms. 1 Males arrive at the colony and settle on nest sites in early spring. Courting and mating takes places somewhere between March and May. It’s up to the male to collect much of the nest material, mostly sticks gathered from the ground, shrubs, trees, or from unguarded and abandoned nests. He presents them to the female and if satisfied with the building materials, she will weave a nest. She makes a flattened platform of sticks with a bowl-shaped nest cup which she lines with pine needles, moss, dry grass, leaves, or small twigs. Nest building can take from 3 days up to 2 weeks and the finished nest can range from a just small platform to multi-year affairs that reach 4 feet across and nearly 4 feet deep. Great blue herons appear blue gray from a distance, with a wide black stripe over the eye and black shoulders. In flight, the upper side of the wing is pale blue on the forewing and darker on the flight feathers. They have an amazing feather system that protects them from oily water. Specially adapted feathers on their chests continually grow and fray and as they fray, they create a powdery substance called powder down. Herons comb the down with a fringed claw on their middle toes (pectinate toes). Together the claw and powder act like a scrubby sponge and cleanser to remove fish slime and oils from their bodies as they preen. During breeding, herons have long wispy plumes on the back and neck that flutter in the wind. The birds have elaborate courtship displays that include neck stretching and twining, greeting squawks, stick transfers, and showy moves where the birds hold their plumes erect and clap their bill tips. Breeding colonies are loud! The great blue heron doesn’t have a melodic song, but they make lots of noise. Pairs greet each other with loud croaks and long grunty roh-roh-roh calls, bill snapping, and clapping. If there’s any kind of threat or disturbance, the colony will erupt with frantic squawks and groans. Herons lay 2 to 6 slightly pale blue eggs in the nest bowl. Incubation is about 28 days. Hatchlings are tiny fuzzy balls of grey feathers and are born with their eyes open. Both adults tend to the chicks and mostly feed them bits of fish, but they will feed them other creatures if fish are in short supply. Parents carry prey in their throat pouches to the nest and then regurgitate the meal into the nest for their young to eat. Young herons may vomit over the side of the nest when alarmed to discourage predators. The nestlings fledge when they are around 7 to 8 weeks old. Parents attend to the young through the summer when the young birds disperse for parts unknown. Juvenile birds are just as big as full adults, but their feathers are blue-grey tinged with Juvenile great blue heron has brown coloring brown. Herons usually start mating behavior in their third spring mixed with the blue-gray feathers. or when they are about 22 months old. Most great blue herons migrate to some extent but are often seen in New Jersey in winter. If they migrate, they generally move southward and always to places with open water. Migration usually occurs 2 mid-September to late October and they return to their breeding colonies by February or March. Herons may migrate on their own, but they have also been seen in groups of up to 100 during migration. The young also migrate but it is unknown if young stay with parents during migration. Parents usually stop interacting with their young in August or September, right around the time when the young leave the area. Great blue herons defend both nesting and feeding territories from other herons with threatening physical displays. The birds go after intruders with their head thrown back, wings outstretched, and bill pointing skyward. Crows and ravens will eat heron eggs. Eagles, raccoons, bears, turkey vultures, and red-tailed hawks prey on the young birds and sometimes even the adults. Birds often abandon a rookery if they have been attacked by predators. Nesting in rookeries is a way for great blue herons to avoid predation. By nesting within a large group, there are many more eyes and ears to keep watch for predators. Also, the chances that one particular nest will be attacked decreases significantly when there is a high density of nests. Still, mortality of young birds is high in the first two years of life, but once they are adults they often live to be 15 year or more. Like most birds, climate change is the biggest unknown when it comes to threats facing herons. As the climate warms, wetlands will be flooded, and they may lose their breeding territories. On the other hand, they may expand their range further north to the arctic. Here is a great online visualization tool to see what happens to their range as the climate warms. Activity: Great Blue Heron Fishing Game Great blue herons have long sword shaped beaks that are ideal for probing mud and catching fish. Their beaks are called striking beaks. In this activity you will pretend you are heron striking your long beak into water to catch your dinner. This is a fun game to play with two or more players. Materials: Salad or pasta tongs = Small toys or natural materials heron beak Pail of water = pond stones, leaves, pinecones, twigs = meals Directions Watch this video of great blue heron hunting for a meal in the water. Listen to the sounds that great blue herons make Fill a bucket or pail with water. If possible, bring the game outdoors Place the small toys/natural materials like pinecones, stones, twigs, and leaves into the bucket 3 Pretend you are great blue heron. Practice opening and closing your “beak” (salad tongs, chopsticks or two sticks joined together with a rubber band can also work, but you will need 2 hands to operate the sticks as a beak Stand 10 to 20 feet away from the pond (bucket of water) Pretend you are a heron and stalk your way to the pond mimicking the movements of the heron in the video you watched earlier. Move like a heron towards the bucket/”pond” When you reach the “pond” open your “beak” and stab it into the water. See if you can “catch” a “meal” on your first try. If not, how many tries does it take you to catch a meal? See if you can catch all the food in the bucket If playing with other people, take turns being the heron and sharing the materials See who catches the most meals or who takes the shortest time to catch a meal Make heron sounds together as if you were a colony of great blue herons! Additional Resources All About Birds; Great Blue Heron Audubon; Great Blue Heron EBird; Great Blue Heron *Photos courtesy of Macaulay Library, Cornell University, Ithaca NY.
Load more

Recommended publications
  • Ardea Cinerea (Grey Heron) Family: Ardeidae (Herons and Egrets) Order: Ciconiiformes (Storks, Herons and Ibises) Class: Aves (Birds)
    UWU The Online Guide to the Animals of Trinidad and Tobago Behaviour Ardea cinerea (Grey Heron) Family: Ardeidae (Herons and Egrets) Order: Ciconiiformes (Storks, Herons and Ibises) Class: Aves (Birds) Fig. 1. Grey heron, Ardea cinerea. [http://www.google.tt/imgres?imgurl=http://www.bbc.co.uk/lancashire/content/images/2006/06/15/grey_heron, downloaded 14 November 2012] TRAITS. Grey herons are large birds that can be 90-100cm tall and an adult could weigh in at approximately 1.5 kg. They are identified by their long necks and very powerful dagger like bills (Briffett 1992). They have grey plumage with long black head plumes and their neck is white with black stripes on the front. In adults the forehead sides of the head and the centre of the crown are white. In flight the neck is folded back with the wings bowed and the flight feathers are black. Each gender looks alike except for the fact that females have shorter heads (Seng and Gardner 1997). The juvenile is greyer without black markings on the head and breast. They usually live long with a life span of 15-24 years. ECOLOGY. The grey heron is found in Europe, Asia and Africa, and has been recorded as an accidental visitor in Trinidad. Grey herons occur in many different habitat types including savannas, ponds, rivers, streams, lakes and temporary pools, coastal brackish water, wetlands, marsh and swamps. Their distribution may depend on the availability of shallow water (brackish, saline, fresh, flowing and standing) (Briffett 1992). They prefer areas with tall trees for nesting UWU The Online Guide to the Animals of Trinidad and Tobago Behaviour (arboreal rooster and nester) but if trees are unavailable, grey herons may roost in dense brush or undergrowth.
    [Show full text]
  • The Grey Heron
    Bird Life The Grey Heron t is quite likely that if someone points out a grey heron to you, I you will remember it the next time you see it. The grey heron is a tall bird, usually about 80cm to 1m in height and is common to inland waterways and coasts. Though the grey heron has a loud “fraank” call, it can most often be seen standing silently in shallow water with its long neck outstretched, watching the water for any sign of movement. The grey heron is usually found on its own, although some may feed close together. Their main food is fish, but they will take small mammals, insects, frogs and even young birds. Because of their habit of occasionally taking young birds, herons are not always popular and are often driven away from a feeding area by intensive mobbing. Mobbing is when smaller birds fly aggressively at their predator, in this case the heron, in order to defend their nests or their lives. Like all herons, grey herons breed in a colony called a heronry. They mostly nest in tall trees and bushes, but sometimes they nest on the ground or on ledge of rock by the sea. Nesting starts in February,when the birds perform elaborate displays and make noisy callings. They lay between 3-5 greenish-blue eggs, often stained white by the birds’ droppings. Once hatched, the young © Illustration: Audrey Murphy make continuous squawking noises as they wait to be fed by their parents. And though it doesn’t sound too pleasant, the parent Latin Name: Ardea cinerea swallows the food and brings it up again at the nest, where the Irish Name: Corr réisc young put their bills right inside their parents mouth in order to Colour: Grey back, white head and retrieve it! neck, with a black crest on head.
    [Show full text]
  • Great Egret Ardea Alba
    Great Egret Ardea alba Joe Kosack/PGC Photo CURRENT STATUS: In Pennsylvania, the great egret is listed state endangered and protected under the Game and Wildlife Code. Nationally, they are not listed as an endangered/threatened species. All migra- tory birds are protected under the federal Migratory Bird Treaty Act of 1918. POPULATION TREND: The Pennsylvania Game Commission counts active great egret (Ardea alba) nests in every known colony in the state every year to track changes in population size. Since 2009, only two nesting locations have been active in Pennsylvania: Kiwanis Lake, York County (fewer than 10 pairs) and the Susquehanna River’s Wade Island, Dauphin County (fewer than 200 pairs). Both sites are Penn- sylvania Audubon Important Bird Areas. Great egrets abandoned other colonies along the lower Susque- hanna River in Lancaster County in 1988 and along the Delaware River in Philadelphia County in 1991. Wade Island has been surveyed annually since 1985. The egret population there has slowly increased since 1985, with a high count of 197 nests in 2009. The 10-year average count from 2005 to 2014 was 159 nests. First listed as a state threatened species in 1990, the great egret was downgraded to endan- gered in 1999. IDENTIFYING CHARACTERISTICS: Great egrets are almost the size of a great blue heron (Ardea herodias), but white rather than gray-blue. From bill to tail tip, adults are about 40 inches long. The wingspan is 55 inches. The plumage is white, bill yellowish, and legs and feet black. Commonly confused species include cattle egret (Bubulus ibis), snowy egret (Egretta thula), and juvenile little blue herons (Egretta caerulea); however these species are smaller and do not nest regularly in the state.
    [Show full text]
  • Great Blue Heron Ardea Herodias
    Great Blue Heron Ardea herodias Throughout the 20th century, Great Blue Herons have been increasing within Ohio. Between 1918 and 1935, Hicks (1935) reported 61 colonies in 33 counties with an estimated statewide population of 1500–2000 pairs. Except for one heronry in Warren County, most of these colonies were confined to the northern half of glaciated Ohio and along the unglaciated plateau in eastern Ohio as far south as Tuscarawas County. However, not all of these colonies were extant at the same time and Hicks was also unaware of some newly established colonies. A large heronry near Fremont was composed of 1118 nests in 1935 (Campbell 1968), indicating that Hicks’ population estimate was probably low. Ohio’s population of Great Blue Herons increased in subse- quent decades, although this expansion was poorly documented. Only Robbins, C. S., et al. (1986) reported a significant increase in Ohio between 1965 and 1979 based on data obtained from the Breeding Bird Survey routes. The current distribution of Great Blue Heron colonies within Ohio was initially surveyed during 1980 and 1981 by the Division of Natural Areas and Preserves. The results of this preliminary survey were expanded during the Atlas Project to produce records of 89 colonies scattered across 52 counties; only these colonies are exhibited on the accompanying map. Every colony was not necessarily active each year, particularly small Mike Williams - ODNR Photographer colonies with 10 or fewer pairs. Additionally, a number of small colonies may have been overlooked. The distribution of breeding Great Blue Heron colonies may be located adjacent to lakes, Great Blue Herons has expanded along the unglaciated Allegheny rivers, and marshes, although inland heronries are frequently Plateau where they are more widely distributed than reported by found in isolated woodlots several miles from any water.
    [Show full text]
  • Bird-A-Thon San Diego County Team: Date
    Stilts & Avocets Forster's Tern Red-tailed Hawk Bird-a-Thon Pheasants & Turkeys Black-necked Stilt Royal Tern Barn Owls Ring-necked Pheasant American Avocet Elegant Tern Barn Owl San Diego County Wild Turkey Plovers Black Skimmer Typical Owls Grebes Black-bellied Plover Loons Western Screech-Owl Pied-billed Grebe Snowy Plover Common Loon Great Horned Owl Team: Eared Grebe Semipalmated Plover Cormorants Burrowing Owl Western Grebe Killdeer Brandt's Cormorant Kingfishers Date: Clark's Grebe Sandpipers & Phalaropes Double-crested Cormorant Belted Kingfisher Ducks, Geese & Swans Pigeons & Doves Whimbrel Pelicans Rock Pigeon Brant Long-billed Curlew American White Pelican Woodpeckers Canada Goose Band-tailed Pigeon Marbled Godwit Brown Pelican Acorn Woodpecker Eurasian Collared-Dove Wood Duck Black Turnstone Bitterns, Herons & Egrets Downy Woodpecker Common Ground-Dove Blue-winged Teal Sanderling Great Blue Heron Nuttall's Woodpecker White-winged Dove Cinnamon Teal Least Sandpiper Great Egret Northern Flicker Mourning Dove Northern Shoveler Western Sandpiper Snowy Egret Caracaras & Falcons Cuckoos, Roadrunners & Anis Short-billed Dowitcher Little Blue Heron Gadwall American Kestrel Greater Roadrunner Eurasian Wigeon Long-billed Dowitcher Green Heron Peregrine Falcon Swifts American Wigeon Spotted Sandpiper Black-crowned Night-Heron New World Parrots Vaux's Swift Wandering Tattler Yellow-crowned Night-Heron Mallard Red-crowned Parrot White-throated Swift Northern Pintail Willet Ibises & Spoonbills Red-maked Parakeet Hummingbirds Green-winged
    [Show full text]
  • Grayson Creek Bird Survey
    Grayson Creek Bird Survey The Grayson Creek Bird Survey is a joint community science project of Friends of Pleasant Hill Creeks and Mt. Diablo Audubon Society. The survey has documented 66 species of native and migratory birds in the Grayson Creek riparian habitat. The Hooded Merganser is a migratory bird that spends the winter in Grayson Creek. The Red-breasted Sapsucker is one of four species of woodpeckers found in the Grayson Creek riparian habitat. The Belted Kingfisher hunts in Grayson Creek. For More Information Birds of Friends of Pleasant Hill Creeks www.pleasanthillcreeks.org [email protected] @PHCreeks Grayson Mt. Diablo Audubon Society www.diabloaudubon.org @mtdiabloaudubon Creek Checklist of Birds in the Cover Photo (Great Egret): Heather Rosmarin Grayson Creek Riparian Habitat The Red-shouldered Hawk nests in the Grayson Red-shouldered Hawk: Andrew Johnson Pleasant Hill, CA All Other Photos: Mick Thompson Creek riparian habitat. It is one of six species of raptors (birds of prey) found in the habitat. The © 2019 Friends of Pleasant Hill Creeks, a project of others are Red-tailed Hawk, Coopers Hawk, Social & Environmental Entrepreneurs, a 501(c)(3) tax- Merlin, American Kestrel, and Turkey Vulture. exempt nonprofit organization. GRAYSON CREEK BIRDS WATERFOWL KINGFISHERS THRUSHES ❑ Greater White-fronted Goose ❑ Belted Kingfisher ❑ Western Bluebird ❑ Cackling Goose ❑ Hermit Thrush ❑ Canada Goose WOODPECKERS ❑ American Robin ❑ Wood Duck ❑ Red-breasted Sapsucker ❑ Mallard ❑ Nuttall's Woodpecker MOCKINGBIRDS ❑ Bufflehead
    [Show full text]
  • Imperiled Coastal Birds of Florida and the State Laws That Protect Them
    Reddish Egret Roseate Spoonbill Threatened (S) Threatened (S) Imperiled Coastal The rarest heron in North Using spatulala-shaped Birds of Florida America, Reddish Egrets bills to feel prey in shallow are strictly coastal. They ponds, streams, or coastal and the chase small fish on open waters, Roseate Spoonbills State Laws that flats. They nest in small nest in trees along the numbers on estuary coast and inland. Having Protect Them islands, usually in colonies barely recovered from with other nesting wading hunting eradication, these birds. This mid-sized heron birds now face extirpation is mostly gray with rust- from climate change and colored head, though some sea-level rise. birds are solid white. Wood Stork Florida Sandhill Threatened (F) Florida Statutes and Rules Crane This large wading bird Threatened (S) is the only stork in the 68A-27.003 Designation and management of the state- This crane subspecies is Americas. Breeding areas listed species and coordination with federal government for resident year-round in have shifted from south federally-listed species Florida, and defends a Florida and the Everglades nesting territory that is northward. Wood Storks 68A-19.005 General Regulations relating to state- must have abundant prey adjacent to open upland designated Critical Wildlife Areas foraging habitat. Nesting concentrated in shallow in shallow ponds, adults wetlands in order to feed 68A-4.001 Controls harvest of wildlife only under permitted defend their eggs or chicks their young. Prey items from predators including include
    [Show full text]
  • (Nematoda: Anisakidae) in Fish-Eating Birds from Zimbabwe
    Article — Artikel First record of Contracaecum spp. (Nematoda: Anisakidae) in fish-eating birds from Zimbabwe M Barsona* and B E Marshalla 2002), of which the reed cormorant Phalacrocorax africanus (Gmelin, 1789), the ABSTRACT white-breasted cormorant P.carbo (L.), the Endoparasites of fish-eating birds, Phalacrocorax africanus, P.carbo, Anhinga melanogaster and darter Anhinga melanogaster Lacapéde & Ardea cinerea collected from Lake Chivero near Harare, Zimbabwe, were investigated. Adult Dauchin, 1802, and the grey heron Ardea Contracaecum spp. were found in the gastrointestinal tract (prevalence 100 % in P.africanus, P. carbo and A. melanogaster;25%inA. cinerea). Parasite intensity was 11–24 (mean 19) in cinerea (L.), were selected because of their P. africanus, 4–10 (mean 7) in P. carbo, 4–56 (mean 30) in A. melanogaster and 2 (mean 0.5) in abundance on the lake. A. cinerea. The cormorants fed mainly on cichlid fishes and carp; the darters and the grey herons on cichlids. All these fishes are intermediate hosts of Contracaecum spp. Scanning MATERIALS AND METHODS electron microscopy revealed that Contracaecum rudolphii infected both cormorant species Four reed cormorants, 4 white-breasted and darters; C. carlislei infected only the cormorants while C. tricuspis and C. microcephalum cormorants, four darters and four grey infected only the darters. Parasites from the grey heron were not identified to species herons were shot with a 0.22 rifle and a because they were still developing larvae. These parasites are recorded in Zimbabwe for the 12-bore shotgun firing buckshot at Lake first time. Chivero. Their beaks were sealed with Key words: Contracaecum, Lake Chivero, mean intensity, nematode, parasite prevalence, rubber bands to prevent the escape of piscivorous bird, Zimbabwe.
    [Show full text]
  • ISMP Guidelines
    Division: Habitat and Species Conservation Authors: Claire Sunquist Blunden and Brad Gruver Report date: December 13, 2018 All photos by FWC unless otherwise acknowledged Presenting 6 new guidelines 1 Guidelines are stand-alone documents that lay out the biological and regulatory needs for each species. The ISMP provides a framework for the Guidelines and details overarching policies, however, each set of Guidelines focuses on individual species (or suites of species). The Guidelines provide species-specific information on: • essential behavioral patterns • survey methods (which are not required but if followed, do provide assurance of species absence) • recommended conservation practices • species-specific exemptions or authorizations for take • coordination with other regulatory programs • permitting options for achieving conservation or scientific benefit The Guidelines also authorize exemptions in some cases so no permits are needed. 2 The 9 species included in this presentation are: • Florida bog frog • Georgia blind salamander • Crystal darter • Southern tessellated darter • Sherman’s short-tailed shrew • Wading birds: little blue heron, tricolored heron, roseate spoonbill, reddish egret These species range from panhandle rivers to a handful of caves in north Florida, to the coastal areas and swamps near the everglades. Each set of guidelines was developed by species experts with input from the public and partners. 3 The Florida bog frog and the Georgia blind salamander are both state Threatened species found in very limited areas of the panhandle. The bog frog is found mainly on Eglin Air Force Base and surrounding public lands, and the Georgia blind salamander is known from a handful of caves and sinks in Calhoun, Jackson, and Washington counties.
    [Show full text]
  • Sacred Ibis (Threskiornis Aethiopicus)1
    Archival copy: for current recommendations see http://edis.ifas.ufl.edu or your local extension office. WEC267 Florida's Introduced Birds: Sacred Ibis (Threskiornis aethiopicus)1 Steve Johnson and Monica McGarrity2 Many non-native birds have been introduced in prey. Sacred Ibises are larger than Florida's native Florida—perhaps as many as 200 species! Of these, ibises. Adults are approximately 30 inches long (75 at least 16 introduced species are considered cm) with a wingspan of 44–49 inches (112–124 established, according to various authorities, and cm) and weigh about 3 pounds (1.4 kg). Sacred Ibises some are now considered invasive and could have (Fig. 1) have mostly white bodies and wings; the serious impacts in Florida. This fact sheet introduces trailing edges of their wings (tips of the feathers) are the Sacred Ibis, and is one of a series of fact sheets gray-black. They have very distinctive long, black about Florida's established non-native birds and their feathers or plumes on their rumps (Fig. 1). During the impacts on our native ecosystems, economy, and the breeding season the feathers on the sides of their quality of life of Floridians. For more information on chests and on the outer wings (near the edge when Florida's introduced birds, how they got here, and the folded) may have a yellowish (or reddish) tinge, and problems they cause, read "Florida's Introduced their lower legs may be tinged with reddish-copper; Birds: An Overview" bare patches of scarlet-red skin may also be visible (http://edis.ifas.ufl.edu/UW297) and the other fact under their wings.
    [Show full text]
  • Responses of Small Herons and Wood Storks to a Changing Prey Base
    Responses of small herons and Wood Storks to a changing prey base Betsy A. Evans, Ashley E. Jackson, Jessica A. Klassen, & Dale E. Gawlik 2019 Greater Everglades Ecosystem Restoration @evanbe01 @FAUAvianEcology Alteration of Everglades hydrology Historic Current • Human development has fragmented the landscape Landscape change • Half its original size, with 70% less water Evergladesplan.org Anthropogenic water bodies Rise of non-native fishes Photos: Alessandro Abate LBHE Kevan Sunderland WOST Kline et al. 2014 Wading bird response 14000 Threatened Legend GA+SC+NC 12000 Florida marsh Endangered Florida urban 10000 What we don’t know: • Population decline due in part to food 8000 How are wading birds resource limitations 6000 responding to these • Storks listed as Endangered in 1984 Number of nests 4000 changes? • Acute decline in small heron nest 2000 numbers over past decade 0 • Uncertainties surrounding decline • However, today, wading birds are moving into urban environments Robertson and Kushlan 1974, Ogden 1994, Hafner 1997, Loftus and Kushlan 1987, Gawlik 2002 Hypotheses In order to examine the influence of non-native fishes and creation of alternative foraging habitats, we examined the diets of three small heron species and Wood Storks: For all wading bird species, we expected the use of non-native species would be highest during suboptimal hydrologic/foraging conditions in the natural marsh Likely due to accessing alternative foraging habitats where non-native species are more prevalent For Wood Storks, we expected that non-native
    [Show full text]
  • Great Blue Heron Facts
    Great Blue Heron At a Glance How can a great blue heron be distinguished from other birds? Scientific Name: Ardea herodias The great blue heron is a large iconic bird of the Chesapeake Bay watershed. The body of the great blue heron is long and narrow covered Body Length: 63 inches in grayish feathers. They have a long grayish neck that can help identify Wingspan: 72 inches them when they are flying. Its head consists of a large black “eyebrow”, yellow to red eyes, and a very long bill with at least some yellow to it. Weight: 4-6 lbs. What do great blue herons eat? Avg. Lifespan: 15 years The diet of the great blue heron consists mostly of fish - any species large Diet: mostly fish, but will also eat enough that it can catch and eat. Blue herons have also been known to amphibians, reptiles, and invertebrates eat amphibians, reptiles, invertebrates, small mammals, and even small birds. Their diet is not picky and they eat basically anything that they can Habitat: swamps, marshes, rivers, swallow. lakes, almost anyplace with fresh to brackish water What predators do great blue herons have? Reproduction: lays 3-5 pale blue eggs Crows and raccoons eat great blue heron eggs. Raccoons, hawks, eagles, Incubation Period: 25-29 days and raccoons occasionally prey on adults and chicks. However, in general Nestling Period: 60 days great blue heron adults are not commonly preyed on due to their large size and the lack of many large predators in North America. Population Status: Least Concern Where do great blue herons live? Great blue herons are found in most of North and Central America.
    [Show full text]