BIRDWALKERMONDAY

Saturday, 6 January 2018

27-3-2017 VILLA LAPAS, COSTA RICA - CRIMSON PATCH BUTTERFLY (Chlosyne janais)

Chlosyne janais, the crimson patch or janais patch, is a common New World butterfly found from Colombia north through Central America and Mexico to southern Texas, with occasional sightings in southeastern Mexico and northern Texas. The dorsal and ventral wing surface is black with several undulating rows of small white spots on the medial forewings and along all outer wing margins. On each dorsal hindwing is a medial orange-red patch situated anteriorly. The ventral hindwings have a fragmented yellow proximal patch bordered by a thick postmedial band of red that does not reach the wing margins; maximum wingspan is 4.8–6.7 cm.

Adults inhabit the periphery of lowland tropical to subtropical forests, fields, and along streams, where they feed on flower nectar. Reproduction is continuous in the tropics, whereas in temperate areas several broods are produced from July to November. The caterpillars are grey white to green with several transverse rows of fleshly black spines; they feed primarily on acanthus shrubs, especially Anisacanthus wrightii and Odontonema callistachus (in Texas), upon which adult females lay their eggs.

The crimson patch can reach high numbers in the Rio Grande Valley, but the population is periodically killed off by cold snaps; the area is then recolonized by members of the Mexican population. A very similar species is the rosita patch (C. rosita), which is distinguished from the crimson patch by the former's lack of spots on the wing margins.

Adults are found along the forest edge of the tropical forest and the surrounding fields.

In the southern most part of their range there are multiple generations each year and adults can be found year round. In the northern part of their flight range multiple generations still occur, but only between the months of July-November.

Populations of Crimson Patch butterflies can build up in significant numbers. Crimson Patch butterflies are, however, greatly affected by weather conditions and on years with colder than usual temperatures the population often plummets.

Adults are found along the forest edge of the tropical forest and the surrounding fields.

Males patrol for receptive females. After mating the females lay their eggs in cluster on host plants. Once the eggs hatch, the early instar larvae feed in groups until they reach their fourth instar. The newly formed pupa hangs from plant matter until it emerges.

27-3-2017 VILLA LAPAS, COSTA RICA - CLAY COLOURED THRUSH (Turdus grayi)

27-3-2017 VILLA LAPAS, COSTA RICA - TROPICAL KINGBIRD (Tyrannus melancholicus)

The tropical kingbird (Tyrannus melancholicus) is a large tyrant flycatcher. This bird breeds from southern Arizona and the lower Rio Grande Valley of Texas in the United States through Central America, South America as far as south as central Argentina and eastern Peru, and on Trinidad and Tobago. Birds from the northernmost and southern breeding areas migrate to warmer parts of the range after breeding.

An adult tropical kingbird is 22 cm (8.7 in) long, weighs 39 g (1.4 oz) and has a wingspan range of 38–41 cm. The head is pale gray, with a darker eye mask, an orange crown stripe, and a heavy gray bill. The back is grayish-green, and the wing and forked tail are brown. The throat is pale gray, becoming olive on the breast, with the rest of the underparts being yellow. The sexes are similar, but young birds have pale buff edges on the wing coverts.

27-3-2017 VILLA LAPAS, COSTA RICA - BARE THROATED TIGER HERON (Tigrisoma mexicanum)

The Bare-throated Tiger-Heron is a bird of tropical swamps. Along the coast, it is typically a mangrove species. It is found, however, in a variety of coastal and freshwater situations, typically characterized as forest edged aquatic habitats. It feeds in coastal lagoons, mangrove swamps, fresh water marshes, swamps, gallery forests along rivers and streams, and wet meadows. It feeds more in the open and in larger habitats than other tiger herons. It is primarily a coastal species occurring below 1,000 m. It avoids human habitats.

The primary foraging behavior of this cryptic heron is Standing in shallow water or on the edge of the water, with neck stretched out diagonally, waiting motionless for long periods. It also Walks slowly, often in situations away from cover. It is a solitary species, usually foraging alone. However a dozen have been seen in a loose group when food is readily available. It is primarily crepuscular but also partially nocturnal. When disturbed it takes flight and perches in a nearby tree. It eats fish, frogs, crabs, and flies.

The breeding season is variable. In Costa Rica nesting may be year round but peaks at the early rainy season (Styles and Skutch 1989). It is May–August in most of its range but February–April in Panama. The tiger heron nests solitarily in trees above the water, especially in mangroves (Rhizophora). Nests are small to large platforms made of sticks usually lined with leaves. They are placed on branches 4-15 m above the ground.

Courtship is little understood in this species, and the displays reported have little context to them (Dickey and van Rossem 1938 Sutton et al. 1950, Wetmore 1965). The primary display appears to be a version of the Stretch—a pair faced each other, necks and bodies crouched horizontally, feathers fluffed up; the birds raise their bills and neck vertically, depressing the neck and body feathers, and emitting two or three hoarse booms or roars. They may sway the neck at the vertical. This may be repeated, and one bird may move toward the other. Mutual Bittern posture has also been described.

Eggs are dull white with a green tinge, rarely flecked with brown or buff. The usually unspotted eggs are not typical of the tiger herons (Dawn 1964). Two measured 56.6 x 43.5 mm and 58.1 x 45.3 mm. Clutches are 1-3 eggs. There is no information on incubation, chick development or fledging and little is known about the nesting success of this species. Nestlings are at risk to hawk (Buteogallus) predation (Lewis and Timm 1991).

The bare throat of this species was recognized for years as being highly distinctive. It is now placed in the same genus as the other two South American tiger herons. The tiger herons are a distinctive lineage of the Ardeidae, adapted to a forest existence. The five species constitute a sister group to all the other herons and bitterns and to the Boat Billed Heron (Sheldon et al. 1995).

The Bare-throated Tiger-Heron occurs in coastal Mexico, Central America, and northern South America.

Breeding range: In Mexico, it occurs as far north as south Tamaulipas and south Sonora, along both coasts, across the Isthmus of Tehuantepec, in all of the Yucatan, coastal in Central America through Panama, including Coida Island and Perles Archipelago but of limited distribution on the Caribbean slope, into extreme north west Colombia from Gulf of Urabá to the lower Atrato River valley.

Friday, 5 January 2018

27-3-2017 VILLA LAPAS, COSTA RICA - JULIA HELICONIAN BUTTERFLY (Dryas iulia)

Dryas iulia (often incorrectly spelled julia), commonly called the Julia butterfly, Julia heliconian, the flame, or flambeau, is a species of brush-footed (or nymphalid) butterfly. The sole representative of its genus Dryas, it is native from Brazil to southern Texas and Florida, and in summer can sometimes be found as far north as eastern Nebraska. Over 15 subspecies have been described.

Its wingspan ranges from 82 to 92 mm, and it is colored orange (brighter in male specimens) with black markings; this species is somewhat unpalatable to birds and belongs to the "orange" Müllerian mimicry complex.

This butterfly is a fast flier and frequents clearings, paths, and margins of forests and woodlands. It feeds on the nectar of flowers, such as lantanas (Lantana) and shepherd's-needle (Scandix pecten-veneris), and the tears of caiman, the eye of which the butterfly irritates to produce tears. Its caterpillar feeds on leaves of passion vines, including Passiflora affinis and yellow passionflower (P. lutea) in Texas.

Its mating behavior is complex and involves a prolonged courtship whose outcome appears to be controlled by the female. This raises questions pertaining to the occurrence of the evolution of sexual conflict.

The species is popular in butterfly houses because it is long-lived and active throughout the day. However, the caterpillars are spiky and may cause a skin rash.

Dryas iulia is characterized by elongated orange wings with black wing markings that vary by subspecies. Black markings are mainly located near the wing tips. Male Julia butterflies can be identified by their brighter orange color, compared to the duller orange exhibited by females .[8] Images of many Julia butterfly subspecies can be found at the bottom of the page.

Dryas iulia is common in the tropical and subtropical areas of North, Central, and South America. In South America, throughout countries like Brazil, Ecuador, and Bolivia, the Julia butterfly is commonly distributed. The butterfly is also widespread throughout a number of the Caribbean islands, with endemic subspecies located in Cuba, Dominica, the Bahamas, and Puerto Rico, among others. Moving further north, the species can be commonly witnessed in Central America up into Texas and Florida (and can occasionally be found to move into the Nebraska area during the summer). The geographic distribution of D. iulia overlaps with the ranges of other butterflies which sometimes leads to conflict. For example, the ranges of D. iulia and the gulf fritillary overlap; in some cases, gulf fritillaries can sometimes be subjected to competition and fighting from Dryas iulia moderata when the two species have breeding populations in similar areas and within the same geographic range.

D. iulia prefer open, sunny breaks in the subtropical and tropical forests it inhabits. The butterfly is also common in open areas such as gardens, cattle grazing lands, and forest clearings, due to human impact. D. iulia can be found on a few main hostplants (or shrubs in Latin America) including the passion vine of the family Passifloraceae.

D. iulia flights take place throughout the year in southern Florida and southern Texas, but especially during the fall. The butterfly in its U.S. range has been seen to occasionally migrate as far north as Nebraska. However, south of its United States range, the Julia butterfly generally does not migrate. The butterfly's flight pattern can be fast or slow, and is usually seen around the middle story of their forest habitat.

Dryas iulia larvae feed on Passiflora plants almost exclusively, specifically those of subgenuses Astrophea (also known as Passiflora), Polyanthea, Tryphostemmatoides, and Plectostemma.

As adults, males and females feed differently based on their reproductive needs. As mentioned further down, males engage in mud-puddling behavior in order to gain valuable minerals for their spermatophores. They have also been seen to agitate the eyes of caimans and turtles in order to produce tears that the butterflies can drink. Observations of this from points 1500 km apart, were probably the first time scientific observations were coordinated via films broadcast on terrestrial television.

27-3-2017 VILLA LAPAS, COSTA RICA - SOCIAL FLYCATCHER (Myiozetetes similis)

The Social Flycatcher, Myiozetetes similis, is a passerine bird belonging to the vast Tyrant Flycatcher family, Tyrannidae. This species is sometimes divided, with Myiozetetes texensis ranging from Costa Rica to Mexico, and Myiozetetes similis proper found from southwest Costa Rica across South America.

Adult Social Flycatchers measure 16–18 cm in length and weigh between 24–27 grams. They exhibit a dark grey head with a striking white eyestripe and an often hidden orange to vermilion crown stripe. Their upperparts are olive-brown, while the wings and tail are brown with faint rufous fringes. The underparts are a vibrant yellow, and the throat is white. Juveniles can be identified by a paler eye mask, a less pronounced crown stripe, and chestnut fringes on their wing and tail feathers. Their call is a sharp "peeurrr," and their dawn song resembles a "chips-k’-cheery."

These birds are found in a variety of open habitats, including plantations, pastures with trees, and open woodlands.

The Social Flycatcher is a common and widespread species, with a range extending from northwestern Mexico to northeastern Peru, southern Brazil, and northwestern Argentina.

Social Flycatchers are known for perching openly on trees, from where they launch to catch insects mid-flight using a range of aerobatic maneuvers. They also hover and glean prey, consume small berries, and may forage on the ground or in shallow waters for aquatic invertebrates, tadpoles, and occasionally small fish. They have been observed foraging alongside common marmosets, possibly cooperating to flush out prey.

Thursday, 4 January 2018

3-1-2018 GANDIA MARJAL, VALENCIA - MALLARD (MALE) (Anas platyrhynchos)

Mallards can be found in almost any wetland habitats, including permanent wetlands such as marshes, bogs, riverine floodplains, beaver ponds, lakes, reservoirs, ponds, city parks, farms, and estuaries. They also occur in prairie potholes and ephemeral wetlands; they may be found feeding along roadside ditches, pastures, croplands and rice fields.

OmnivoreMallards are generalist foragers and will eat a wide variety of food. They don’t dive, but dabble to feed, tipping forward in the water to eat seeds and aquatic vegetation. They also roam around on the shore and pick at vegetation and prey on the ground. During the breeding season, they eat mainly animal matter including aquatic insect larvae, earthworms, snails and freshwater shrimp. During migration, many Mallards consume largely agricultural seed and grain. In city parks, they readily accept handouts from parkgoers.

3-1-2018 GANDIA MARJAL, VALENCIA - LITTLE EGRET (Egretta garzetta)

3-1-2018 GANDIA MARJAL, VALENCIA - GREYLAG GOOSE (Anser anser)

3-1-2018 GANDIA MARJAL, VALENCIA - GREY HERON (Ardea cinerea)

3-1-2018 GANDIA MARJAL, VALENCIA - GREAT TIT (Parus major)

3-1-2018 GANDIA MARJAL, VALENCIA - EUROPEAN ROBIN (Erithacus rubecula)

3-1-2018 GANDIA MARJAL, VALENCIA - EUROPEAN MOORHEN (Gallinula chloropus)

3-1-2018 GANDIA MARJAL, VALENCIA - DOMESTIC GREYLAG GOOSE (Anser anser var. domesticus)

Tuesday, 2 January 2018

21-3-2017 HOTEL BOUGANVILLEA, COSTA RICA - TROPICAL KINGBIRD (Tyrannus melancholicus)

Tropical kingbirds appear to be monogamous. In most parts of the species' range, they are permanent residents and remain together in pairs year-round.(Sibley 2014)[page needed] The call is a high-pitched twittering trill, tree-e-e-e-e-e-e, with a more complex version sung by the male at dawn.

Their breeding habitat is semi-open areas with trees and shrubs, including gardens and roadsides. Tropical kingbirds like to observe their surroundings from a prominent open perch, usually high in a tree, undertaking long flights to acrobatically catch insects in mid-air (hawking), sometimes hovering to pick food off vegetation (gleaning). The insects preyed upon include beetles, bees, wasps, termites, butterflies, moths, dragonflies and grasshoppers. They also eat some berries and fruit from such diverse species as tamanqueiro (Alchornea glandulosa), common guava (Psidium guajava), the Annonaceae, Cymbopetalum mayanum and gumbo-limbo (Bursera simaruba); foraging for these even in disturbed habitat. As they keep mainly to the upper levels of trees, they find little profit in following mixed-species feeding flocks in the understory.

Aplomado falcons have been known to prey on adult tropical kingbirds, while eggs and young have been attacked by swallow-tailed kites and chestnut-mandibled toucans. These birds aggressively defend their territory against intruders, even much larger birds such as magnificent frigatebirds, toucans, caracaras or hawks. In a study in Parque Nacional de La Macarena of Colombia, parasitism by microfilariae and trypanosomas (presumably T. everetti) was infrequently recorded in tropical kingbirds.

The male and female inspect potential sites together before selecting a site, typically a fork or crotch high in a tree (up to 20 m (66 ft) high) but sometimes just a few metres above water.(Sibley 2014)[page needed] The female builds a bulky, sloppy-looking, shallow nest of vines, rootlets, twigs, weeds, and grasses; it is unlined or lined with hair. Nests average about 13.2 cm (5.2 in) across and 7.6 cm (3.0 in) tall, with interior cup about 7.6 cm (3.0 in) across and 4.1 cm (1.6 in) deep.

The female incubates the typical clutch of two to four eggs for approximately 16 days, and the nestlings fledge in another 18 or 19 days. The eggs are whitish or pale pink with variable amounts of dark blotching.

21-3-2017 HOTEL BOUGANVILLEA, COSTA RICA - CLAY COLOURED THRUSH (Turdus grayi)

The clay-colored thrush (Turdus grayi) is a common Middle American bird of the thrush family (Turdidae). It is the national bird of Costa Rica, where it is well known as the yigüirro (Spanish: [ʝi'ɣwiro]). Other common names include clay-colored robin.

It ranges from South Texas (where it is rapidly expanding its range) to northern Colombia. West and north of the Isthmus of Tehuantepec, it is limited to the Atlantic slope, except for a population around Oaxaca City, Mexico that probably originates from escaped cage birds. In much of its range it is familiar in yards and gardens, similar to some other thrushes such as the American robin, the Eurasian blackbird, and the song thrush.

In general appearance and habits it resembles other Turdus thrushes such as the American robin. It is about the same length or slightly smaller: 23–27 cm (9.1–10.6 in), and weighs 74–76 g (2.6–2.7 oz) on average. The plumage is brownish, somewhat lighter below than above, lightest on the flanks. Birds from humid regions are darker than those from dry regions. The throat is faintly streaked. Immature birds have faint mottling on the back and underparts. The bill is greenish-yellow with a dark base, the legs are pinkish or flesh-colored, and the irises are reddish—all useful identification points.

23-3-2017 HOTEL BOUGAINVILLEA, COSTA RICA - BLUE GREY TANAGER (Thraupis episcopus)

The Blue-gray Tanager, Thraupis episcopus, is a medium-sized songbird of the tanager family, Thraupidae. It presents a delightful palette of blue hues, with a light bluish head and underparts, and darker blue upperparts. A distinctive shoulder patch, varying in color among subspecies, adds to its charm. Both sexes are similar in appearance, with the immature birds showing a much duller plumage.

Adults measure between 16–18 cm in length and weigh approximately 30–40 grams. They possess a short and quite thick bill. The shoulder patch coloration is a key feature for identification, ranging from lavender to dark blue or white, depending on the subspecies.

The Blue-gray Tanager is found in open woodlands, cultivated areas, and gardens. It is a species that has adapted well to human-altered landscapes.

This species has a broad range, extending from Mexico through Central America, South America to northeast Bolivia, and northern Brazil, encompassing all of the Amazon Basin except its southernmost part. It has also been introduced to Lima, Peru, and is native to the islands of Trinidad and Tobago.

The Blue-gray Tanager is known for being a common, restless, and confiding bird, often seen in pairs or small groups. It is quite at home in human habitation and is known to partake of cultivated fruits such as papayas.

21-3-2017 HOTEL BOUGAINVILLEA, COSTA RICA - BALTIMORE ORIOLE (FEMALE) (Icterus galbula)

The Baltimore oriole (Icterus galbula) is a small icterid blackbird, a migratory breeding bird common in eastern North America. The male's vibrant orange and black plumage is reminiscent of the coat-of-arms of the 17th-century Lord Baltimore, hence the name. This medium-sized passerine typically measures 17–22 cm in length with a wingspan of 23–32 cm. Adults are characterized by white bars on the wings, with males boasting a more pronounced orange hue on the underparts, shoulder patch, and rump, while females and juveniles display a more subdued yellow-brown and dull orange-yellow coloration.

Orioles primarily feed on insects, berries, and nectar. They are adept at foraging in trees and shrubs and are known to sip at hummingbird feeders. They play an important ecological role by consuming pests such as the forest tent caterpillar moth.

Males are distinguished by their black head and back with bright orange to yellow-orange underparts and a solid black tail. Females and juveniles are less boldly colored, with a mix of brown and orange hues. All adults have distinctive white wing bars, which are useful for identification from a distance or in flight.

Baltimore orioles favor open woodland, forest edges, and partially wooded wetlands. They are also found in orchards, farmland, urban parks, and suburban areas with woodlots. During winter, they inhabit flowering canopy trees, often over shade coffee plantations.

The Baltimore oriole breeds from the Canadian Prairies and eastern Montana eastward through southern Canada and the eastern United States, migrating to winter in Central America and northern South America. They are rare vagrants to Western Europe.

Outside of mating season, Baltimore orioles are solitary. They are monogamous, though extra-pair copulation is not uncommon. Males establish territories in the spring and perform various displays to attract females. After mating, the female weaves a remarkable hanging nest where she lays her eggs.

The male's song is a series of sweet whistles, while calls include a nasal "veeer" and a low chatter. Females also sing, especially when defending their nests. Both sexes emit specific warning calls during confrontations.

Baltimore orioles are generally monogamous and solitary outside the breeding season. The female constructs a hanging, pouch-like nest at the end of a branch, where she lays 3-7 eggs. Both parents feed the nestlings, which fledge after about two weeks.

The Baltimore oriole may be confused with the Bullock's oriole, but the latter has a more western distribution. Other similar species include the Scott's and Audubon's orioles, which differ in their coloration and range.

The Baltimore oriole is currently listed as Least Concern by the IUCN. However, its population has experienced a decline due to factors such as habitat loss and Dutch elm disease, which has reduced nesting sites.