It’s spring and our local pigeons (Columba livia) are prancing in courtship. The males bow and coo to their chosen mates and accompany their ladies in flight. When their courtship is successful the males clap their wings.
You can hear cooing and wing clapping in this audio clip …
Wild turkeys introduce themselves to each other on a personal basis but when it comes to where they live humans get involved.
Last summer eBird revised their species maps to show “introduced” versus “native” ranges of all the birds. For North American species that have been introduced elsewhere in the U.S. the results were bi-colored orange and purple maps. See maps for introduced house finches and bobwhites at Common Birds, Exotic Ranges.
Apparently wild turkeys were introduced, too. So how do the native turkeys stay neatly on their own side of the Washington-Idaho border? Don’t they introduce themselves to the other guys?
according to ebird turkeys are hyper-aware of political boundaries, and i imagine there is a brutal ongoing conflict between introduced turkeys (in orange) and native turkeys (in purple) for control of the west pic.twitter.com/Lu9x6tTkKg
Wild turkeys are ancestors of the domestic turkeys we eat on Thanksgiving. Understandably, wild turkeys avoid humans but in rare instances a male becomes aggressive toward people. This happens because turkeys are social birds.
Wild turkey (Meleagris gallopavo) flocks have a social structure called a pecking order that’s especially important during the breeding season in March to May. Dominant males puff and strut and confront other males to maintain their own dominance. If a subordinate gets out of line the dominant turkey struts and gobbles at him, pecks him, or flies at him with spurs exposed. Notice the spur below.
A dominant male who is acclimated to people may mistake us as subordinates and try to put us in our place. Occasionally one becomes fixated on bicycles and the cyclists riding them(*).
In one case in Livermore, California an aggressive wild turkey made a motorist’s day. A policeman stopped a speeding driver and was going to issue a ticket but a wild turkey saw the motorcycle and challenged the police officer.
Massachusetts Division of Fisheries and Wildlife has advice on how to prevent wild turkey aggression toward people.
Aggressive behavior towards people occurs when turkeys have become overly comfortable in the presence of humans, usually over several months or even years, in areas where turkeys are fed. [For this reason] Never intentionally leave out food like bird seed or corn in attempts to help or view turkeys.
If our city pigeons were this beautiful, would we take them for granted?
The pink-necked green pigeon (Treron vernans), a native of Southeast Asia and Indonesia, is a fruit-eating forest bird well adapted to human landscapes. Graced with the colors of a pastel rainbow, the male is sometimes called the rainbow dove.
Despite the female’s camouflage, nesting safely is a challenge. When she sees a threat approaching she opens her wings to look larger but her display doesn’t scare off the male Asian koel (Eudynamys scolopaceus) who successfully steals her eggs. (Despite their appearance Asian koels are cuckoos, not crows.)
As for the pigeons, they will court and lay a new clutch very soon.
In spring a change occurs in mourning dove behavior as large flocks we see in winter disperse to nest. Some flocks move north while locals break up into couples and fan out to choose a territory.
It is hard to notice when the change occurs so I graphed my eBird count of mourning doves (Zenaida macroura) in Frick and Schenley Parks, January 2021 through 9 April 2022.
The change is pretty dramatic. Just 1-5 birds from March through September, then over 40 December through February. The largest flocks were at the Frick Environmental Education Center where they sunned in the trees above the feeders. 100 mourning doves in January!
This year the count dropped below 10 in early March as they paired up. Some pairs maintain their bonds throughout the winter. Others get to know each other in the spring.
According to Birds of the World: To build the nest he brings small twigs, etc. which he delivers to her while standing on her back(!) She arranges them around her while using her body to form a simple bowl. Nest building usually takes 7–10 hours spread over 2–4 days.
The loosely built nest looks messy. Sometimes you can see through it from below.
And they mate. She lays her first egg within 2 days of nest completion. Subsequent eggs are one or two days apart.
Mourning dove pairs share incubation as they wait for the eggs to hatch in 14 days. Surprisingly neither bird has a brood patch but it works anyway.
The chicks are fed by regurgitation and grow up to resemble their parents. They fledge in 13-15 days, sooner if frightened.
Juveniles remain in speckled plumage through August. By winter they look like adults.
And in October mourning doves gather in flocks again. The process starts over from flocks to nests.
UPDATE 13 April 2022: Today at Frick Park I talked with someone who has a mourning dove nest in their yard while 16 mourning doves hung out near the feeders. Flocking and nesting were simultaneous today.
(photos from Wikimedia Commons; click on the captions to see the originals)
Avian influenza, also called bird flu, is in the news lately because a highly contagious strain has made it to North America from Eurasia. Though not dangerous to humans, this year’s strain is easily caught by some bird species, most notably chickens. Here’s what it is and what we can do to protect birds.
What is this virus?As USDA explains, “Avian influenza is caused by an influenza type A virus which can infect poultry (such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl) and wild birds (especially waterfowl).” Various strains are always in the wild but the low pathogenicity versions do not cause illness in wild birds or chickens. Every few years, however, a highly pathogenic (HPAI) strain surfaces that is extremely infectious, fatal to chickens, and rapidly spreads in domestic poultry.
This year’s HPAI strain has already devastated many poultry farms.
Which birds have died? USDA is tracking the virus and reports that millions of commercially raised chickens and turkeys have already died this year. As of 7 April 2022 the total death count was more than 24.2 million, the vast majority of which — more than 16 million — were Commercial Layer Chickens. That’s why the price of eggs has gone up. (See USDA commercial and backyard flock statistics here.)
Should we worry about wild birds? Not so much. Wild birds maintain their own social distancing whereas domestic poultry live in crowded conditions on factory farms.
In addition, avian flu is primarily caught by ducks, geese, swans, chickens, wild turkeys, pheasants and quail. Some raptors catch it, though in low numbers. Songbirds are at low risk.
As of 7 April 2022, USDA testing of dead wild birds has found 637 cases in the U.S. 88% were water-related birds, notably mallards and snow geese. 11% were raptors. The highest raptor death toll was among black vultures who roost communally. (See USDA wild bird statistics here.)
Notice the order of magnitude here: 24.2 million poultry deaths versus 637 wild bird deaths.
Interestingly, the species most susceptible to avian influenza are closely related and stand alone in the the phylogenomic supertree below (pale green branch at bottom right) while those least susceptible are least related to ducks and chickens.
And finally, here are two quotes from the New York Times:
Nearly all the nine billion chickens raised and slaughtered in the United States each year can trace their lineage to a handful of breeds that have been manipulated to favor fast growth and plump breasts. The birds are also exceptionally vulnerable to outbreaks of disease. “They all have the same immune system, or lack of an immune system, so once a virus gets inside a barn, it’s going to spread like wildfire,” said Dr. Hansen, the public health veterinarian.
Andrew deCoriolis, the executive director of Farm Forward says: “Instead of asking how factory farms can prevent infections that originate in the environment, which is how they frame it now, we should be asking how they can prevent infections that originate on factory farms,” he said. “If we keep raising more and more animals in these conditions, we should expect the exact outcome we’re getting because that’s how the system is set up.”
In January the PA Game Commission kicked off of their largest ever study to count and track wild turkeys (Meleagris gallopavo) in Pennsylvania.
Pennsylvania’s wild turkey population has varied over the years from near extirpation in the early 1900s to a recent peak in 2001. The birds move around. When this graph began in 1995 there were probably no turkeys within the city limits of Pittsburgh. Now they are fairly common in Pittsburgh’s suburbs and the City’s large parks and greenways.
Since wild turkeys are game birds, PGC has always tracked the annual harvest numbers but now, to better understand turkey population dynamics, they will band more birds and track the movements of hens. To do so they will temporarily trap a flock to apply bands and, in WMUs 2D, 3D, 4D and 5C, they will tag 100 hens with transmitters. Click here for a WMU boundary map.
The PA Game Commission is asking the public to help locate flocks for the project. Report the location of any turkey flock you see between now and 15 March 2022 at this link: https://pgcdatacollection.pa.gov/TurkeyBroodSurvey. Rest assured that the project is not going to hurt or move any turkeys as PGC explains:
Birds are being leg-banded for population and research purposes ONLY.
GPS transmitters will be put on 100 hens in 4 WMUS (25 in each).
All turkeys trapped will be released on site – they will NOT be moved.
Location data are only used for research purposes (not law enforcement).
I’m tempted to enroll Frick’s and Schenley’s wild turkeys because I’d love to find out where they come from and where they go but they’re probably not eligible for the study. However we may learn the origin of new recruits when we see banded turkeys in the years ahead.