scholarly journals Organochlorine-Associated Immunosuppression in Prefledgling Caspian Terns and Herring Gulls from the Great Lakes: An Ecoepidemiological Study

1996 ◽  
Vol 104 ◽  
pp. 829 ◽  
Author(s):  
Keith A. Grasman ◽  
Glen A. Fox ◽  
Patrick F. Scanlon ◽  
James P. Ludwig
Keyword(s):  
Great Lakes ◽  
Herring Gulls ◽  
Caspian Terns

Great Lakes Caspian Terns: Egg Contaminants and Biological Implications

1985 ◽  
Vol 8 (2) ◽  
pp. 142 ◽  
Author(s):  
John Struger ◽  
D. Vaughn Weseloh
Keyword(s):  
Great Lakes ◽  
Caspian Terns

Metals and Essential Elements in Herring Gulls from the Great Lakes, 1983

1987 ◽  
Vol 13 (1) ◽  
pp. 43-55 ◽  
Author(s):  
J. Struger ◽  
J.E. Elliott ◽  
D.V. Weseloh
Keyword(s):  
Great Lakes ◽  
Essential Elements ◽  
Herring Gulls

Seasonal Distribution and Site Fidelity in Great Lakes Caspian Terns

1988 ◽  
Vol 11 (2) ◽  
pp. 202 ◽  
Author(s):  
Louis L'Arrivee ◽  
Hans Blokpoel
Keyword(s):  
Great Lakes ◽  
Site Fidelity ◽  
Seasonal Distribution ◽  
Caspian Terns

Embryonic abnormalities and organochlorine contamination in double-crested cormorants (Phalacrocorax auritus) and Caspian terns (Hydroprogne caspia) from the upper Great Lakes in 1988

1993 ◽  
Vol 79 (2) ◽  
pp. 163-173 ◽  
Author(s):  
Nobuyoshi Yamashita ◽  
Shinsuke Tanabe ◽  
James P. Ludwig ◽  
Hiroko Kurita ◽  
Matthew E. Ludwig ◽  
...  
Keyword(s):  
Great Lakes ◽  
Phalacrocorax Auritus ◽  
Upper Great Lakes ◽  
Caspian Terns

Intraclutch egg-weight apportionment and chick survival in Caspian terns

1986 ◽  
Vol 64 (10) ◽  
pp. 2116-2122 ◽  
Author(s):  
James S. Quinn ◽  
Ralph D. Morris
Keyword(s):  
Body Size ◽  
Great Lakes ◽  
Potential Benefit ◽  
Brood Reduction ◽  
Chick Survival ◽  
Egg Weight ◽  
Parental Response ◽  
Main Effect ◽  
Caspian Terns ◽  
Negative Effect

Egg-weight apportionment patterns and chick survival were investigated in two-egg clutches of Caspian terns(Sterna caspia) in the Great Lakes. First-laid eggs (A eggs) were typically heavier than second-laid eggs (B eggs) and hatched an average of 1.8 days earlier. The A-egg fraction of total clutch weight increased with total clutch weight. Increased egg weight did not increase the probability of hatching, but did increase the fledging success of A chicks: specifically, A eggs that produced fledglings were significantly heavier than those whose chicks did not fledge. No such relationship held for B eggs. The main effect of B-egg weight was in prolonging life: excluding those few that fledged, egg weight was correlated significantly with age at mortality. Chick mortality appeared to be due mainly to starvation and gull predation. We suspect that greater body size and (or) behaviour associated with body size helps chicks escape risk from gape-limited predators. The hatching of A eggs had a negative effect on the survival of B chicks, but the reverse was not true. B offspring may act as insurance against the loss of A siblings. The potential benefit to parents of investing more in B eggs appears to be constrained by sibling competition with A chicks, which often results in brood reduction. The pattern of egg-weight apportionment in eggs is interpreted as a parental response to the differences in the reproductive values of asynchronously hatching chicks.

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