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D. H. Ellis

Publications and source records attributed to D. H. Ellis.

At least 73 records · Page 4Linked to original sources
USGS1995

A new tether system for captive raptors

Several types of jesses are used to restrain captive raptors. The Hollywood jess described here has been tested on six species during two decades. Like the Aylmeri jess now in common use in North America, the Hollywood jess consists of a removable rolled button jess and an anklet. Unlike the Aylmeri anklet, however, the Hollywood anklet can be removed and reattached without restraining the bird. This anklet makes the Hollywood jess the safest of all jesses. It can also be used repeatedly on different individuals and allows for the bird to be released in its pen or to the wild without encumbrances.

Journal of Field Ornithology↗
USGS1994

The natural history of Caroline Atoll, Southern Line Islands. Part II. Seabirds, other terrestrial animals, and conservation

conclusion: Lushly wooded Caroline Atoll, with the majority of its 39 islets (399 ha of land) either in near-pristine condition or having recovered remarkably from past disturbance, is one of the least spoiled atolls in the Pacific. Uninhabited, it harbors plant ecosystems and breeding seabirds (Pt. II) of national and international importance. Its marine and terrestrial ecosystems are prime outdoor ecological laboratories for research on geological processes including ground water, sea level changes, the dynamics of motu formation, fish poisoning, and numerous facets of ecology including plant succession and Pisonia growth rates. Caroline boasts prime coral reefs thickly studded with Tridacna clams, substantial numbers of coconut crabs, breeding sites for green turtles, wintering grounds for shorebirds including the rare Bristle-thighed Curlew, ancient Tuamotuan marae, and a crystalline, unpolluted lagoon. The variety, abundance, and quality of its flora and fauna qualify it for status as an officially recognized international preserve (Pt. II, Sect. G). Efforts toward its conservation have thus far been unsuccessful: in 1992 it was leased to a private French businessman who is currently fishing the reefs for commercial profit, as well as disturbing seabird, turtle and coconut crab populations.

Atoll Research Bulletin↗
USGS1994

Should we terminate an 'artificial,' tree-nesting raptor population in Arizona?

The Altar Valley in southcentral Arizona was once a iallgrass prairie. Overgrazing prevented fire and spread mesquite, allowing the area, now a savanna, to be heavily used by tree-nesting raptors in summer and heavily hunted by perch-hunting raptors in winter. The breeding raptor community (over 150 pairs) consists primarily of red-tailed hawks (Buteo jamaicensis), great horned owls (Bubo virginianus), and Swainson's hawks (Buteo swainsoni). Common ravens (Corvus corax) are also common and there is a recently discovered small population of black-shouldered kites (Elanus caeruleus). Recent efforts to restore the endangered masked bobwhite (Colinus virginianus) to the area clash with habitat needs of the raptors. This conflict focuses attention on the 'multiple use' concept and calls for implementation of a 'prime use' or 'highest and best use' management strategy. Prime use (this is the only area in the United States managed for the masked bobwhite) 'will likely call for the removal of trees over much of the Altar Valley. This removal will likely result in the nearly total loss of nesting and perching sites for breeding, migrating, and wintering raptors.

Journal of Raptor Research↗
USGS1994

Harpy eagle (Harpia harpyja) nesting in manipulated forests

Continental records point to shooting, removal of young and destruction of nests as the primary conservation problems for harpy eagles (Harpia harpyja); bird-observer visits are a new source of concern. Nesting events are roughly 3 yr apart. Nests are used during and after intensive manipulation of the surrounding habitat, and minimum distance between active sites was 3-5 km. In nine nesting sites along a 100-km stretch of the Imalaca Mountains in Venezuela, we fitted five fledglings with satellite-tracked tags from NASA. One of these birds was hacked with the help of the loggers who destroyed its nest. All these nests were active while logging ensued. Out of three renesting attempts, one failed when the nest collapsed. We salvaged two additional fledglings found in captivity. We are monitoring five nests in the buffer area of the Darien National Park in Panama, all within 3 km of human settlements where trees are regularly felled for firewood, lumber, and to clear more cropland. Eagles have been killed at two sites, a third site remains inactive since 1991, and the other two nests currently have fledglings.

Journal of Raptor Research↗
USGS1994

Diurnal raptors in the fragmented rain forest of the Sierra Imataca, Venezuela

The rain forest of the Sierra Imataca in eastern Venezuela has been subjected to extensive deforestation for pastures and agricultural settlements. In the last decade the opening of access roads combined with intensified logging and mining activities have fragmented a significant portion of the remaining forest. We noted local distribution and habitat use for 40 species of diurnal raptors observed in ten affected areas, including raptors considered as forest interior species and some open country species utilizing the man-made openings inside the forest for roosting and foraging.

Journal of Raptor Research↗
USGS1994

A fall land bird migration across the South China Sea from Indo-China to the Greater Sunda Islands

We encountered 150 land birds representing 14 families along the cruise track of the Soviet Oceanographic Research Vessel AKADEMlK KOROLEV in the South China Sea. We saw most of these birds during a 3 -day period in a small area c. 350 km southeast of the southern tip of the Indo-China peninsula. These observations suggest that a significant land bird migration corridor crosses the South China Sea from Viet Nam to Borneo.

Journal of the Bombay Natural History Society↗
USGS1993

Satellite telemetry options for avian research

Four manufacturers now produce transmitters in the size range suitable for raptors (3-5% of body mass). Dummies of these transmitters will be displayed and harnessing techniques will be demonstrated. Estimates will be given for: cost, reliability, longevity, mass, availability, programmability, power output and other information essential in deciding on manufacturer and model.

Journal of Raptor Research↗
USGS1993

Telemetry via satellites for raptor studies

Monitoring animal movements by satellite was first ac complished in 1970 with an elk in Wyoming. The large size of early transmitter packages restricted their use to very large animals. Miniaturization of electronic components in the 1980s allowed application of satellite telemetry to large birds. Satellite transmitters have been tested with mixed results on geese, swans, petrels, bustards, eagles, and falcons. Dramatic weight reduction in the 1980s was quickly followed by tests of a variety of transmitter shapes on captive birds. Research on attachment methods helped in selecting those methods least likely to elicit adverse behavior. Wind tunnel experiments were conducted to produce more aerodynamically efficient PTT designs. Recently, the utility of satellite tracking has been demonstrated in studies of wandering albatrosses in the Indian Ocean, migrating Bewick's swans, bald eagles, and golden eagles. Two other studies demonstrated the feasibility of tracking cranes by satellite. The types of information from these techniques will be presented and cross-referenced to a poster display and demonstration.

Journal of Raptor Research↗
USGS1992

Behavior of sandhill cranes harnessed with different satellite transmitters

The effectiveness of various attachment methods and designs of platform transmitting terminals (PTT's) was tested on captive sandhill cranes (Grus canadensis) at the Patuxent Wildlife Research Center, Laurel, Maryland, during 1989-91. Combinations of attachment and transmitter designs included neoprene cord harness with batteries separate from the transmitter (2 harness designs), Teflon ribbon harness with batteries incorporated into the transmitter package (4 transmitter models), and a package attached directly to the bird with epoxy glue only. Physical effects seen on cranes wearing PTT's ranged from skin lacerations (caused by rubbing of harness material) to no observed effects (other than feather wear). The most successful harness material and design utilized a Teflon ribbon harness with the 4 ribbon ends from the transmitter forming a neck loop and a body loop joined at the sternum. Time spent by sandhill cranes performing most activities did not change after transmitter attachment using this harness method.

Book chapter↗
USGS1992

Progress in satellite tracking cranes

We review the history of tracking cranes with satellite telemetry and identify some of the difficulties in designing satellite transmitters and harnesses for cranes. Miniaturization of these transmitters and a plethora of harnessing experiments since 1989 allow us to recommend limited application of this technology to all species of cranes. We are still uncertain, however, if cranes harnessed with satellite telemetry devices are able to reproduce after migration. Because of this uncertainty, we urge caution in the use of this technology, especially with breeding adults in severely endangered populations. This manuscript also describes continuing research needs.

Book chapter↗