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Ornithology

2001

Mortality

Articles 1 - 4 of 4

Full-Text Articles in Life Sciences

Mortality Of Whooping Crane Colts In Wood Buffalo National Park, Canada, 1997-99, Douglas G. Bergeson, Brian W. Johns, Geoffrey L. Holroyd Jan 2001

Mortality Of Whooping Crane Colts In Wood Buffalo National Park, Canada, 1997-99, Douglas G. Bergeson, Brian W. Johns, Geoffrey L. Holroyd

Proceedings of the North American Crane Workshop

Twenty-two whooping crane (Grus americana) pairs with 2 young were monitored in Wood Buffalo National Park (WBNP) over 3 years to determine causes of colt mortality. The family groups were monitored from the ground, air, and with the aid ofradioteiemetry. We attached transmitters to 18 colts: 5 (28%) fledged, 5 (28%) succumbed to cumulative effects (head trauma, stress, exposure and/or infection), 4 (22%) were lost to unknown causes (3 of these went missing after they had lost their transmitters), 2 (11%) were taken by foxes (Vulpes vulpes), 1 (5.5%) was lost to raven (Corvus corax …


Using Ivermectin To Increase Survival Of Sandhill Crane Colts At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Caroline P. Herziger Jan 2001

Using Ivermectin To Increase Survival Of Sandhill Crane Colts At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Caroline P. Herziger

Proceedings of the North American Crane Workshop

Parasitic gapeworms (Cyathostoma sp.) caused 5.6% of mortalities of219 radiomarked greater sandhill crane (Grus canadensis tabida) colts at Malheur National Wildlife Refuge (NWR) in Oregon from 1991-98. From 1993-98 we tested the efficacy of ivennectin, an antihelmenthic drug, as a means of increasing colt survival by reducing gapewonn infestations. We selected pairs of siblings for the study, injecting 1 colt with ivennectin and not the other. We found significantly shorter survival times for untreated birds compared to those treated with ivennectin (P = 0.06). We conclude that in areas with gapewonn infestations in young cranes, the …


Egg Collection And Recruitment Of Young Of The Year In The Aransasi Wood Buffalo Population Of Whooping Cranes, John R. Cannon, Brian W. Johns, Thomas V. Stehn Jan 2001

Egg Collection And Recruitment Of Young Of The Year In The Aransasi Wood Buffalo Population Of Whooping Cranes, John R. Cannon, Brian W. Johns, Thomas V. Stehn

Proceedings of the North American Crane Workshop

We present data for 61 years (1938 to 1998) on the recruitment of juvenile (i.e., young-of-the-year) whooping cranes (Grus americana) for the 1 natural wild population that nests in the vicinity of Wood Buffalo National Park (WBNP) in Canada and migrates annually to wintering grounds in the vicinity of Aransas National Wildlife Refuge (ANWR) on the Gulf coast of Texas in the United States. We divide these years into 2 data sets: years during which 1 of 2 eggs was collected from WBNP nests (to develop captive populations and to conduct reintroduction experiments), and years during which no …


Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding Jan 2001

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.