Showing posts with label Female Songbird Project. Show all posts
Showing posts with label Female Songbird Project. Show all posts
Sunday, June 5, 2022
Sunday, February 2, 2020
Friday, September 7, 2018
Oklahoma Breeding Bird Species Profile: Gray Catbird
This video on assorted avian mimicked voices was a remarkable rendition by a California Gray Catbird. Never have I heard such accomplished material, for this is what I would expect from an older bird that has seen many breeding seasons. A bird like this could easily have his choice of mates, for a female would easily realize how special he really is for the valuable syrinx that he has.
A uniform gray bird with a black cap, long black tail and rufous undertail coverts, this is a gorgeous and remarkable bird once it opens its mouth.
Common to uncommon in brushy thickets in woods, along forest edges, parks, often in damp shaded areas, as well as generally solitary. However, the exception is when the male sings from an exposed perch to attract a female or protect his territory. This species forages at ground level for berries, insects, and other invertebrates.
Gray Catbird
South Padre Island, TX 2015
Mimic thrushes like this are talented, as well as natural mimics, and one of ten in the Mimidae family. The harsh mew of this bird is especially diagnostic in the field, especially if heard near the ground. Females also sing, though rarely, and not nearly at as much of a volume. Catbirds, like Northern Mockingbirds, often sing at night.
Rather tame, it will respond readily to pishing calls and will come quite near.
Catbirds are late spring migrants, arriving on breeding grounds from May to June, and fall migration is between late August and September. Birds residing on the coast sometimes choose not to migrate.
The Brown-headed Cowbird parasitizes this species, but may not in Oklahoma. In other locations, the female simply ejects cowbird eggs. The territoriality of the Grey Catbird is restricted to the area of the nest site. The female does most of the nest building, though the male will provide the supplies. He will even actually point out possible sites by sitting on branches and moving twigs about as though constructing a nest. Incubation is solely by the female. The male doesn't feed her very much during this time. The species is known to double brood.
Thursday, August 9, 2018
Oklahoma Winter Bird Profile: Rusty Blackbird
Known as a bird with a light iris, the Rusty Blackbird is uncommon and can be found in Oklahoma in winter, if you are lucky. Though drab and a loner, they once darkened the skies, much like the now extinct Passenger Pigeon.
A breeding bird of the boreal forest, this blackbird has been declining in population since the middle of last century for unestablished reasons. One possibility is the loss of habitat in wintering regions in the southeast, where most of the species is located during that time.
Birds of the northeast have been showing high concentrations of mercury, not unusual where coal happens to be a source of heat and powering electrical plants. If that fossil fuel becomes reestablished, chances are good that it will destroy the remaining populations, unless it relocates itself elsewhere.
Rusty Blackbirds forage on the ground and will wade in water in order to turn over leaves and twigs while seeking insects, which could also have high mercury concentrations. Some of Oklahoma's lakes and other larger bodies of water can be suspect, especially around the Sooner Lake power plant, which is still partially coal fired.
Rusty Blackbird
Boomer Lake Park, 2016
Logging in the winter ranges around bogs, fens and other wet methane reaches of spaghnum moss, the mechanical sound of a rusty hinge can be heard. This is the sound of the Rusty Blackbird, which was once ubiquitous at the turn of the 1900s.
Climate change is no doubt playing a part in the loss of this population. The rain comes and goes, their favorite invertebrates choked out by their loss of habitat, excess heat and cold, or any other negative effects. Either their food departs for cooler or warmer climates as the seasons change, or they migrate to possibly even less favorable conditions.
Acid rain is likely another suspect in some of this mystery, because it was caused by the combustion of fossil fuels. It is due to the emission of sulfur dioxide and nitrogen oxides. Also, we must look at the effects of toxic algal blooms, which destroys ecosystems that these birds favor, and that's where pesticide runoff will accumulate, which can also kill the inhabitants of these systems. A stronger case is the Dead Zone in the Gulf of Mexico, which is spreading to their wintering areas.
What is most necessary is the preservation of crucial wetlands, less disturbance, and more birders to seek out their habitats and report their findings to the International Rusty Blackbird Working Group during select spring migrations and on eBird.
In the winter, the rusty seeks pine seeds, acorns, and whatever available fruit it can locate.
They can be found on edges of lakes or ponds, in pecan orchards, agricultural areas, flooded forests, swamps, flooded roadside ditches, and the like.
Rusty Blackbird(s) have been seen during most winters at Sanborn or Boomer Lakes from 2013-2018.
Thursday, July 19, 2018
Oklahoma Breeding Bird Species Profile: Bell's Vireo
Cheedle-cheedle-chew, Cheedle-cheedle-chee!
Male Bell's Vireo
Late April to early May is the time of year to be hearing that classic call around the Kentucky coffeetree, ficus, and willow thickets of central Oklahoma, as long as we are near water and dense shrubby ground.
Male Bell's Vireo In Ficus Tree
The adult male is first in his territory, calling at the tops of trees. He will establish an acre to two acre territory, which he will share with a mate and his young. Song is constant over a two week period after spring arrival in mid-May, until female arrives and this is followed by a short courtship period, where song is still at a fairly high rate. Several nests are built, including dummy nests to detract the Brown-headed Cowbird, who lays in wait for the first month in order to locate and predate the chosen nest. Nests have been easy to find, as the songs continue and become faster in tempo at this location. When eggs have been laid, the song wanes and then occurs much less often.
Female Bell's Vireo with Nesting Material
This species boasts four subspecies, the Eastern, Western, Arizona, and the intermediate West Texas birds. The Eastern are brighter yellow and olive with a shorter tail than the western, and will bob the tail. The Westerns flip the slightly longer tail up and sideways, in the gnatcatcher fashion. Western populations are divided into the California, or Least Bell's Vireo, and the Arizona race.
These shy birds are uncommon and declining, and are generally solitary, unless breeding. The species is very territorial, and stays low within vegetation. They feed upon larvae and insects.
They have never been observed drinking water, which could be provided by their choice of food, as well as during the bathing process.
The species has an elaborate repertoire of calls ranging from about a second to nearly five seconds. Naturally this includes the alarm call, a threat-in-area notification, morning and approaching night songs, nestbuilding, intrusion, courtship, and several others. For the Female Songbird Project, the female has been heard to produce a short answer call. The purpose of this designation appears to be for male and female communication is the absence of either vireo. This is very similar to the same practice of the Northern Cardinal, which is well known to all birders.
Courtship is an interesting affair, as the male perches and calls for anywhere from a week or two, then suddenly, a female appears. This was the first time that it was learned that females have a singing voice, as she would answer from the nest spot. She would rarely show herself and even when young were fledging, a young bird was usually seen before she was.
Bell's Vireo with caterpillar
There is no sexual dimorphism in the species, and the female is clearly the submissive bird. It is always the male that initiates attack toward intruding birds. The Northern Cardinal is no threat, Mourning Doves are ignored, as are both Baltimore and Orchard Orioles, as well as the Red-winged Blackbird. Carolina Chickadees are chased and driven from the area.
Nests are well concealed by dense foliage, and are usually no more than three feet from the ground. They are never seen near the trunk, but are located upon the ends of lateral forks, which can easily be seen in the fall or winter.
In good years, two broods are possible. If there is any human disturbance, such as construction, birds will relocate and if early enough in the season, they will renest. Light pole construction was done in June of 2018, and the family relocated in a southerly direction, but it is uncertain if there was a new nest.
Bell's Vireo Fledgling
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