Peregrine Falcon Recovery Project (Manitoba)

Peregrine Falcon

The name "peregrine" means wanderer, and the Peregrine Falcon has one of the longest migrations of any North American bird. Tundra-nesting peregrines winter in South America, and may move 25,000 km (15,500 mi) in a year.

scientific name: Falco peregrinus other names: Duck Hawk, Faucon pèlerin (French), Halcón peregrino (Spanish)

There are 19 recognized subspecies of peregrine falcons around the world, three of which live in Canada though only two, anatum and tundrius, can be found in Manitoba. The differences (other than genetics) between subspecies are size and colouration.

Anatum - known as the American Peregrine Falcon, or "Duck Hawk"; its scientific name means "wandering duck falcon". Larger and darker than tundrius, smaller and lighter than pealei. Northern breeding anatum tend to migrate south into Central and South America, southern breeding anatum overwinter in their breeding ranges. Anatum suffered greatest population decline of all three North American subspecies and was the focus of recovery/reintroduction efforts in Canada and the USA in the 1980s and 90s. Tundrius - is the smallest and lightest coloured of the North American peregrine subspecies. It is found in the Arctic tundra of North America and Greenland. Subspecies is highly migratory and overwinters in South America. Pealei - also known as Peale's Falcon and is the largest and darkest of the North American peregrines. It is found in the Pacific Northwest north through British Columbia into Alaska and along the Aleutian Island Chain into Siberia. It is non-migratory.

description

Peregrines are a medium-to-large falcon and like all true falcons, they have a pointed "tooth" on it's upper beak and a "notch" on the lower. They have long, pointed wings and tail, a compact head and beak and large feet and talons. Males and females look alike with the major difference in appearance being between adults and juveniles.

adults: slate-grey back with a dark hood on the head and dark facial stripes exteding from the eye across the malar (hence malar stripe or sometimes "moustache") with white cheekpatches; underparts are pale (whitish, grayish or buffy) with black speckles and horizontally barring; feet and toes are yellow. juveniles: dark brown upperparts, gold underparts with darkbrown vertical barring on breast and belly; dark hood on head with a thinner malar stripe than the adults and often with gold on the crown and top of head; legs and toes are pale yellow or more often a light bluish grey.

Peregrines display reversed sexual dimorphism, that is, females are larger than males - they are 15-20% longer and 40-50% heavier.

length: females are 45-58cm and males 36-49cm / 36–49 cm, female 45–58 cm. wingspan: 74-120cm weight: females 900-1500g (), males 450-800g

habitat

Peregrines most commonly prefer habitats that contain cliffs for nesting and open landscapes for foraging. In Canada they seem to prefer no particular landscape though perhaps there are higher densities on the tundra and coastally.

breeding habitat: may breed up to elevations of 3,600m in the Rocky Mountains; elsewhere dispersion follows rivers or shorelines of coasts and lakes as nestsites are usually associated with water; built-environments such as urban areas with buildings and other structures are used. habitat use on migration: make use of a broad range of urban and natural habitats; prefer "leading lines" such as barrier islands, seacoasts, lake edges or mountain ranges. wintering habitat: extreme variability in habitat because of the peregrines' enormous geographic range; urban areas increasingly host wintering birds particularly in eastern Canada and New England; overwintering birds in the US Midwest use a habitat devoid of cliffs; coastal wetlands are favoured in Mexico and high deserts in Peru and Chile.

hunting + food habits

Peregrines have long been known as the fastest bird in the world but this occurs only when they are "stooping" while hunting. Peregrines hunt on "the flat" in direct pursuit of their prey or diving after their prey from high altitude (300-3,000 feet) which is called stooping. Peregrines grab their prey or strike it with their closed feet hard enough to stun or kill it outright. They then catch the bird and use their powerful beak to break their prey's neck to kill it.

Peregrines can be hunting at any time of the day but they greatly prefer to hunt at dawn and dusk when their prey is most active. In recent years, urban peregrines have been observed hunting at night using the light generated by the city infrastructure. During the nesting season adults will cache extra food to ensure they have enough for their growing chicks as well as their own needs.

average traveling flight speed - 40-55 km/h (25-34 mph) level pursuit speed - 112 km/h (69 mph) maximum speed during a stoop - 320 km/ (238 mph)

Peregrines prey primarily on birds though they have been found to prey on bats and occasionally small mammals if the mammal population is high, for example near bat caves and hibernacula. In North America, 450 species of birds have been documented as peregrine prey and it is estimated that worldwide, the number may be as high as 2,000 species. According to the Birds of North America, peregrines have been "observed killing birds as large as a Sandhill Crane, as small as a hummingbird and as elusive as a White-throated Swift". The typical peregrine diet includes waterfowl, shorebirds, pigeons (particularly for urban falcons) and songbirds.

	For Manitoba's urban-dwelling peregrines, 60% of their diet consists of
		Rock Doves/Pigeons Sora Rails Northern (Yellow-shafted) Flickers Black-billed Cuckoos

breeding

Peregrines are sexually mature at one to five years on average but usually don't start breeding until three or four years of age, earlier for females, later for males. Pairs mate for life, which means they will remain together for as long as they return each spring. If their mate doesn't return, the survivor will find a new mate, often the same year. Pairs return to the same nestsite annually. Courtship includes aerial acrobatics and mid-air food transfers.

Peregrines nest on cliffs ranging from 25-1,300 feet though some pairs nest in higher locations where conditions allow. They choose nest ledges that are large enough for growing chicks and are protected from terrestrial predators. Where cliffs aren't available, peregrines find nestsites with these same attributes on buildings, bridges, communications towers, etc. Because breeding pairs are territorial, their nests are a considerable distance apart which also ensures sufficient food for the adults and chicks. Peregrines don't build a nest per se, rather they make a bowl-shaped "scrape" in the sand or gravel on their chosen ledges, no nest materials are added to the scrape. In urban areas where nestboxes have been installed for the peregrines, gravel is provided. The male will make multiple scrapes for the female to choose from.

number of broods: 1 per year clutch size: 2-5 eggs, 3-4 is most common egg description: about the size of a chicken egg; pale creamy to brownish in colour or blotched with brown, red or even sometimes purple incubation period: 29-32 days, slightly longer if weather is cold condition at hatching: helpless, eyes closed, covered with white down and weighing about 40 grams (1.5oz) age at fledging (first flight): 35-45 days, earlier for male chicks, later for females

Egg-laying occurs in April and May in Manitoba and the chicks hatch about a month later. If eggs are lost early in the incubation period, a pair may re-nest. Both the adults share incubation duties though the females tend to most, particularly at night. Chicks fledge six weeks after hatching. Despite an average of 3-4 eggs being laid, only 2.5 chicks generally survive to fledge age and the average number of chicks per nest that fledge successfully is 1.5. After fledging, chicks remain dependent on their parents for up to two months more. Usually by the end of September/beginning of October, both the adults and chicks begin their southward migrations.

longevity + mortality

In the wild, juvenile peregrines have a high mortality rate. In the first year, 50-70% of young peregrines die due to accidents, misadventure injuries, predation or starvation. If they survive their first year however, their mortality rate drops significantly and a healthy peregrine will live another 12 years on average.

	The oldest wild peregrine on record was "James" who nested on the James River Bridge in Virginia, USA. He was 20 years and 5 months old when he was last seen.
	The oldest Manitoba peregrine was also a male who was a hackmate of our first Radisson male. He was released in downtown Winnipeg in 1986 and was not seen again until he was found dead, again in Winnipeg in January 2004 at the age of 18 years and 9 months.
	The longest known lifespan for a captive peregrine falcon is 25 years.

Causes and rates of mortality for both adult and juvenile peregrines living in human environments are similar to those living in non-human environments though some causes occur more often in one environment than the other. The most common cause of death is exposure to wet and/or cold weather when the chicks are very young. And while nestboxes can help reduce weather-related mortality, they will never be able to prevent it entirely. The next most common cause is collisions which in human environments includes human structures and vehicles and while collisions may be occur more often in human environments, they are often occur in non-human environments. Conversely, predation due to avian predators Great Horned Owls, eagles, Gyrfacons and other peregrines), and occationally mammalian predators, is almost non-existent in human environments. Deaths due to disease, parasites, starvation/dehydration, drowning, electrocution, poisoning shooting and plane strikes are also reported, but are not common. One advantage in human environments is that ill or injured birds can be more easily found, rescued and potentially rehabilitated and returned to the wild.

Deaths resulting from conflict with another peregrine is commonly due to territorial rivalry and from reports, this cause of death increases as breeding density and population pressures increase, a natural, but unfortunate consequence of recoverying peregrine populations.

conservation

North American and European peregrine populations suffered a catastrophic decline beginning in the 1950s. This decline was related to the use of the organochlorine pesticides such as DDT and DDE which caused the eggshells to thin so much that they cracked or were crushed during incubation. DDT and related pesticides and were developed and used to kill agricultural insects after the Second World War and they was very effective. What wasn't anticipated at the time was that these chemicals would have a toxic persistence in the environment or that the accumulated residues in the tissues of birds and mammals would have deleterious effects. The pesticides were sprayed on crops to then be eaten by insects and the insects died. However, many species of birds also eat the crops and others ate the insects and the pesticide accumulated in the birds' boddies. In turn, peregrines hunted these smaller birds the residue in their prey likewise accumulated in the falcons' bodies. The result was that the residue reduced the amount of calcium laid down in the eggshell by the females and fewer eggs survived to hatch. In North America, anatum populations were extirpated in the continental USA and there were only a few known nests in Canada south of the 60th parallel.

In the mid to late 1960s, the extent of the peregrine decline was confirmed and the causes identified. The extent of the decline was so catastrophic that scientists and falconers joined forces to save the species by seeking a ban on the use of DDT and to find ways to reintroduce the species in areas where they had disappeared. The agricultural use of DDT was banned in Canada in 1970 and the USA in 1972 though the use of existing stocks of DDT continued until the mid-1980s and DDT can (and has) still be used to combat public health emergencies. Similar restrictions also exist in Mexico but many countries in South and Central America continue to use the pesticide, which means that peregrines and their prey are still exposed to DDT during a part of their life. Bans in the peregrines' breeding range have been essential for the species' long-term survival, but these bans are controversal because DDT is seen as the best defence against malaria-deaths worldwide.

There was no legal protection for peregrines in North America before the 1930s and in fact they were often seen as pests because they preyed on gamebird species of value to humans. By the 1950s/60s, most states and provinces had some legislation in place to protect peregrines from being taken from the wild but there was no such thing as an endangered species until the passage of the US Endangered Species Conservation Act in 1969. The peregrine falcon was officially listed as an endangered species in 1970 under this Act. In Canada, federal, provincial and territorial governments agreed to list species as "at-risk" through the new Committee on the Status of Endangered Wildlife in Canada (COSEWIC) developed in 1977 under the Canada Wildlife Act. The Committee is composed of representatives from government, academica and non-government organizations and is supported by taxonomic sub-committees. The anatum peregrine falcon was listed as "endangered" and the tundrius as "threatened" by COSEWIC in 1978. This formalized the government's responsiblity to protect species (and later their habitat) and also meant access to funding. In Manitoba, the anatum and tundrius subspecies were jointed designated as "endangered" in 1992 under the province's Endangered Species Act.

Recovery efforts in Canada began in the late 1960s with a development of a captive-breeding program coordinated by the Canadian Wildlife Service (CWS). After a number of years of trial and error (no one had ever bred peregrines for this purpose before), the program was successfully raising "wild" chicks in captivity. To reintroduce these chicks into the wild, the program employed a proven release technique employed by falconers. Captive-bred chicks were successfully "hack-released" at sites across the country starting in the mid-1970s. Manitoba's Peregrine Falcon Recovery Project began with the release of four captive-bred chicks in Winnipeg in 1981. Between 1975 and 1996 (when the CWS breeding facility was closed) over 2,000 captive-bred chicks were hacked or fostered in wild nests in Canada. Another 5,000 were similarly released in the continental USA.

Over thirty years later, there are between 2,000 and 3,000 breeding pairs of anatum peregrine falcons in Canada, the US and Mexico. As a result of recovery peregrine populations, tundrius peregrines were downlisted by "vulnerable" by COSEWIC in 1992 and anatum were downlisted to "threatened in 1999. Also in 1999, all peregrine falcon subspecies were de-listed (removed) from the US Endangered Species List. In 2012 anatum and tundrius peregrines were again downlisted, this time designed as species of "special concern", which is the lowest "at-risk" designation under the federal Species-at-Risk Act (SARA). All of Canada's peregrines are also protected at the national and international level is under the international Migratory Birds Convention Act and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) which (very simply) prohibits the possession or exportation of species-at-risk and their products in whole or in part.

	Peregrine Falcons have never been a common species in Manitoba in large part due to the lack of suitable nesting habitat. With the growth of urban areas however, more habitat is now available and the peregrines have responded positiviely.
	Are there more peregrines in Manitoba now than there were before the crash in 1950s and 60s? Impossible to know.
	We don't know how many, if any, tundrius peregrines nest in Northern Manitoba. We do know that there are two stable anatum nestistes in the southern half of the province, the first at the Radisson Hotel in downtown Winnipeg, the second in Brandon at the McKenzie Seeds Building. There have been other nestsites over the years but these sites has not been "passed down" from one pair to next which is key, particularly with our very small population of peregrines in the province.
	As a result, the peregrine falcon, both anatum and tundrius, is still designated as "endangered" in Manitoba.

references

For more information on peregrine falcons, please check out the links below.