scholarly journals Decline in breeding of the Great Black-backed Gull, Larus marinus, and the Herring Gull, L. argentatus, on Boot Island, Nova Scotia, 1986 to 2010

2014 ◽  
Vol 128 (2) ◽  
pp. 165 ◽  
Author(s):  
Colin M. MacKinnon ◽  
Andrew C. Kennedy
Keyword(s):  
Nova Scotia ◽  
American Mink ◽  
Bald Eagle ◽  
Haliaeetus Leucocephalus ◽  
Herring Gull ◽  
Quarter Century ◽  
Bird Colony ◽  
Great Blue Heron ◽  
Larus Marinus ◽  
Landfill Management

For over 50 years, Boot Island, Nova Scotia, has supported a significant mixed bird colony: Great Black-backed Gull (Larus marinus), Herring Gull (L. argentatus), Great Blue Heron (Ardea herodias), and Double-crested Cormorant (Phalacrocorax auritus). In 2002, the largest Great Black-backed Gull colony in Canada was located there. Over the last quarter century, the Herring Gull colony has shown a dramatic and near-linear decrease from 727 nests in 1986 to 67 in 2000; in 2010, only two nests remained. The number of Great Black-backed Gull nests has also declined by 44%, from 1467 nests in 1992 to 819 in 2010. These reductions may be partly attributed to factors external to the colony, such as changes in regional fisheries and better landfill management. However, a more immediate problem may be nest predation and disturbance by American Mink (Neovison vison), Raccoon (Procyon lotor), Coyote (Canis latrans), and Bald Eagle (Haliaeetus leucocephalus).

scholarly journals Bald Eagle, Haliaeetus leucocephalus, Preying on Maritime Garter Snake, Thamnophis sirtalis pallidulus, on Cape Breton Island, Nova Scotia

2006 ◽  
Vol 120 (4) ◽  
pp. 477
Author(s):  
Storrs L. Olson
Keyword(s):  
Nova Scotia ◽  
Bald Eagle ◽  
Garter Snake ◽  
Haliaeetus Leucocephalus ◽  
Thamnophis Sirtalis ◽  
Cape Breton Island ◽  
Cape Breton

At 1053 hours on 23 July 2006 a Bald Eagle, Haliaeetus leucocephalus, was observed in flight transporting in its talons a live Maritime Garter Snake, Thamnophis sirtalis pallidulus, at South Harbour (46°52'01.7"N, 60°26'45.8"W), Cape Breton Island, Victoria County, Nova Scotia.

Recent switch by the Great Blue Heron Ardea herodias fannini in the Pacific northwest to associative nesting with Bald Eagles (Haliaeetus leucocephalus) to gain predator protection

2013 ◽  
Vol 91 (7) ◽  
pp. 489-495 ◽  
Author(s):  
I.M. Jones ◽  
R.W. Butler ◽  
R.C. Ydenberg
Keyword(s):  
Reproductive Success ◽  
Pacific Northwest ◽  
Close Association ◽  
Bald Eagle ◽  
Haliaeetus Leucocephalus ◽  
Bald Eagles ◽  
Safe Place ◽  
Ardea Herodias ◽  
Great Blue Heron ◽  
The Pacific

The Great Blue Heron Ardea herodias fannini Chapman, 1901 in the Pacific northwest appears to have modified nesting behaviour in response to the strong recent recovery of the Bald Eagle (Haliaeetus leucocephalus (L., 1766)) population. Previously undescribed, herons now often nest in close association with some breeding eagles, even though eagles depredate heron nestlings, are implicated in the recent reproductive decline of herons, and may induce abandonment of heron breeding colonies. We tested the hypothesis that breeding herons gain protection from the territorial behaviour of eagles. Natural observations and simulated incursions showed that nesting eagles actively repel other eagles within at least 250 m around the nest site, thereby establishing a relatively safe place for herons to nest. Surveys showed that 70% of heron nests and 19% of heron colonies were located within 200 m of eagle nests with high reproductive success. These herons had greater reproductive success than those nesting far from eagle nests.

Using a Conservation Biology Blueprint to Protect Seven Species found in the Frontenac Arch Biosphere Reserve, Canada

2018 ◽  
Author(s):  
Alexandra Kelly ◽  
Monica Seidel
Keyword(s):  
Endangered Species ◽  
Conservation Biology ◽  
Biosphere Reserve ◽  
Bald Eagle ◽  
General Distribution ◽  
Black Rat ◽  
Great Blue Heron ◽  
Spotted Turtle ◽  
Rat Snake ◽  
Provincial Park

This project developed a conservation biology blueprint for the Frontenac Arch Biosphere Reserve (FABR) region that can be used towards assessing current conservation practices as well as making future recommendations. The findings of the study can be used towards the Ten Year Biosphere Review for UNESCO, which the FABR submits to keep their biosphere designation. By gathering information in real time, appropriate actions can be taken much more quickly than if the information was only gathered every ten years. This means that different actors can alter their actions to preserve species diversity and success as different factors influence those species through time. For this study, seven species (bald eagle, red-headed woodpecker, common five-lined skink, black rat snake, milksnake, spotted turtle, and great blue heron) were mapped in the area between Frontenac Provincial Park and Charleston Lake Provincial Park. The black rat snake, spotted turtle, and great blue heron were specifically explored in an online survey as well. This study area was chosen on the suggestion of the FABR because it connects Crown Land with the provincial parks, making implementing any new policies easier than land found in the North-South corridor of Ontario which contains a high amount of private development. Using the predicted tree species data, county land usage, eBird data, and endangered species general distribution, this paper hopes to identify where key areas of protection are. By quickly locating hotspots for endangered species, stricter conservation regulations can be implemented to help the recovery of these species.

Bilateral Malignant Seminoma With Ventricular Metastasis in a Bald Eagle (Haliaeetus leucocephalus)

2018 ◽  
Vol 32 (3) ◽  
pp. 240-245
Author(s):  
Patrick J. Sullivan ◽  
Olufemi O. Fasina ◽  
Andrew C. Cushing. BVSc
Keyword(s):  
Bald Eagle ◽  
Haliaeetus Leucocephalus

Bald Eagle Lead Exposure in the Upper Midwest

2014 ◽  
Vol 5 (2) ◽  
pp. 208-216 ◽  
Author(s):  
Sarah E. Warner ◽  
Edward E. Britton ◽  
Drew N. Becker ◽  
Michael J. Coffey
Keyword(s):  
Lead Poisoning ◽  
Lead Exposure ◽  
Clinical Signs ◽  
Local Environment ◽  
Bald Eagle ◽  
Haliaeetus Leucocephalus ◽  
Upper Midwest ◽  
Bald Eagles ◽  
Potential Source ◽  
Liver Lead Concentration

Abstract In 2012, we examined lead exposure in 58 bald eagles Haliaeetus leucocephalus found dead in Iowa, Minnesota, and Wisconsin. We determined lead concentrations in livers, examined differences in exposure among ages and between sexes, and recorded clinical signs consistent with lead poisoning. Most (60%) of the bald eagles had detectable lead concentrations, and 38% of the 58 had concentrations within the lethal range for lead poisoning. We found no differences in exposure based on sex or age, but we did find an inverse relationship between body and liver mass and liver lead concentration. The high percentage of lead-exposed bald eagles encouraged us to further examine potential sources of lead in our local environment. We initiated a study on the Fish and Wildlife Service's Upper Mississippi River National Wildlife and Fish Refuge to investigate if discarded offal piles from hunter-killed deer were a potential source of lead exposure to scavenging wildlife such as the bald eagle. Radiographs showed that 36% of offal piles in our sample area contained lead fragments ranging from 1 to 107 particles per pile. Our study indicated that 1) lead exposure rates for bald eagles found dead in our Upper Midwest study area were high, 2) more than one-third of the bald eagles found dead in Iowa, Minnesota, and Wisconsin had liver lead concentrations consistent with lead poisoning, and 3) discarded offal piles from deer shot with lead ammunition can be a potential source of lead exposure for bald eagles.

Central Nervous System B-cell Lymphoma in a Bald Eagle (Haliaeetus leucocephalus)

2018 ◽  
Vol 32 (1) ◽  
pp. 40-44
Author(s):  
Marike Visser ◽  
Heather Walz ◽  
Stephanie Shrader ◽  
Jey Koehler ◽  
Jamie Bellah
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
B Cell ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Bald Eagle ◽  
Haliaeetus Leucocephalus

Effects of Egg Oiling on Larid Productivity and Population Dynamics

The Auk ◽  
1984 ◽  
Vol 101 (3) ◽  
pp. 584-592 ◽  
Author(s):  
Stephen J. Lewis ◽  
Richard A. Malecki
Keyword(s):  
Hatching Success ◽  
Oil Pollution ◽  
Mortality Rates ◽  
Breeding Birds ◽  
Fuel Oil ◽  
Herring Gull ◽  
Embryo Survival ◽  
Larus Marinus ◽  
Nest Materials ◽  
Dose Responses

Abstract Small quantities of petroleum may adhere to the plumage, feet, or nest materials of breeding birds and be transferred to their eggs during incubation. In this study, oil was applied to naturally incubated Great Black-backed Gull (Larus marinus) and Herring Gull (L. argentatus) eggs, and its effects on reproductive success were assessed. Embryo survival was inversely proportional to the quantity of petroleum applied to eggshell surfaces. Dose responses, however, were dependent on embryonic age at the time of treatment. Eggs of either species, treated with 10-20 μl of No. 2 fuel oil 4-8 days after laying, experienced significant reductions in hatching success. Embryos oiled past the midpoint of the 28-day incubation period were insensitive to as much as 100 μl of petroleum. Fuel oil weathered outdoors for several weeks was as toxic as fresh oil to larid embryos. Productivity estimates obtained following various oil treatments indicated that only under severe conditions (e.g. large doses of petroleum contaminating young embryos) could egg oiling have a significant impact upon populations of the Herring Gull and species with similar life-history characteristics. Species that are more sensitive to oil, however, those having lower reproductive potentials and higher postfledging mortality rates or those subject to other stresses, may be more adversely affected by oil pollution.

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