Longevity of Saskatchewan Birds

S?N oJ8 fter 42 years of banding, an unexpected satisfaction has been the accumulating records of bird longevity.To get such worthwhile results, banding must be selective.From my experience, I would like to offer words of both encouragment and caution to younger banders.First, as has been said by many others, the "ring and fling" technique of banding any and every bird that one can catch, in an unplanned and haphazard fashion, is of no benefit to science.Such banding just clogs up the big computer in the banding office at Patuxent Refuge, and provides no long-term satisfaction to the bander.I admit that I began as just such a "promiscuous" bander, but I hasten to add that this adjective does not apply to my marital life.Indeed my wife Mary is my longestserving subpermittee.While we mist-netted for a few years and banded hundreds of thrushes and warblers, we failed to receive a single recovery from these birds.On the other hand interesting recoveries kept coming in from birds of prey, from waterfowl, and from colonial birds.We gradually changed our emphasis and thereby increased the value of our banding, as we reduced the number of species banded from a yearly high of 94 species to a low of 33 species.We have now had 2440 recoveries to the end of 1984, from 87,056 birds of exactly 200 species banded until that time.Repeats and returns are not included in these figures.Since the raptors and colonial birds are banded as flightless young, their exact point of birth is known, making subsequent recoveries more valuable in a scientific sense.The recovery rate for Great Horned Owls, Golden Eagles, Red-tailed Hawks, Northern Goshawks and Ospreys runs over 6% as do the rates for American White Pelicans and Double-crested Cormorants.Gulls banded in Saskatchewan run at 2% with Common and Caspian Terns close to 1%.Some winter birds such as Bohemian Waxwings and Black-capped Chickadees, Purple Finches, and Evening Grosbeaks also run in the neighborhood of 1%.Some of these rates will rise slightly as older birds are reported in future years.Mary continues to band virtually all the Tree Swallows and Mountain Bluebirds raised in the 250 houses forming our part of the Prairie Bluebird house trail, but here the results are measured in returns, not recoveries.Banders usually wait only a few years to learn where many of their birds go.But to learn how long birds live, a bander must wait considerably longer.And the number of banded birds remaining alive is meanwhile decreasingø ly inexorably.In the last 12 years I have received an unusual number of recoveries that help flesh out the right hand side of life tables where numbers are always small.Some hold the longevity record for their species.I wish to tell of each in turn.My Great Horned Owl 508-0890, banded at Bredenbury, Saskatchewan on 17 May 1959 and caught in a trap at Roblin, Manitoba on 4 December 1972, at 13 years 6 months was the oldest record of this species for 4 years.Then an owl banded by D. Seal of Rockford, Illinois was found freshly dead 17 years and four months after banding.A computer printout from Patuxent in November 1984, brought word of three remarkably old Great Horned Owls in one mail.I contacted each finder at once to confirm the bird's exact date of death, without giving any intimation that longevity was my concern.518-60341 had been banded in its nest near Saskatoon on 10 May 1967 and was found freshly dead near Delisle, Saskatchewan on 17 June 1984 was 17 years, 1 month old.518-60395 was banded near St. Benedict on 14 May 1967 and was hit by a motor vehicle near Hendon on 30 July 1983.It was 16 years, 2 months old and had moved only 60 miles (90 km) southeast.518-60767 had been banded near Lepine Siding on 4 May 1968.It was found freshly dead on a snowdrift beside Max Hackl's barn near St. Benedict on 23 March 1984, at the age of 15 years, 10 months.This owl, preserved in the farmer's deep freeze, was autopsied at the Western College of Veterinary Medicine.It was emaciated and apparently had starved to death.In 1973 I learned that Black-crowned Night Heron 547-24244, banded as a nestling on 7 July 1956 near Craven, had been found on a fence apparently unable to fly near the Cape Romain Wildlife Refuge, Awendaw, South Carolina.It died that night at the age of 16 years, 7 months, and 8 days.This was a short-lived record, and was eclipsed before I could publish it.Less than five months later on 9 July 1973 a Black-crowned Night Heron, banded as a nestling near the southwest corner of Lake Erie, was collected for pesticide analysis within 30 miles of its banding place.It had been banded on 6 June 1952 and was slightly more than 21 years old.

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