Status and Reproductive Success of the Caspian Tern (Sterna caspia) in the U.S. Great Lakes

Abstract

Caspian Tern (Sterns cas ia,) breeding colonies exhibit a disjunct distribution on all continents except South Er?-er ca where they apparently do not nest. On the North American continent,

Trends in Caspian Tern Numbers and Distribution in North America: A Review

“…During 1987-1998, the Caspian Tern bred at scattered localities across North , b e r i c a . Banding data suggest that birds nesting west of the continental divide, along the Gulf Coast and in the Great Lakes, form three separate populations (Ludwig 1965(Ludwig , 1968Shugart et al 1978;Gill and Mewaldt 1983). It is not known if immigration/emigration occurs between these populations and breeding populations in central Canada and along the Atlantic coast; however, the latter form geographically distinct units.…”

Indirect Negative Impacts of Double-crested Cormorant (Phalacrocorax auritus) Management on Co-nesting Caspian Terns (Hydroprogne caspia) in Northern Lake Michigan, USA

“…Our study suggests that cormorant management caused indirect negative impacts on terns. As the Great Lakes tern population is considered isolated from other regional populations and is maintained primarily through reproduction (Hyde 1996), an unsuccessful breeding season potentially impacts regional population viability (Shugart et al 1978). Any future cormorant control actions must consider how, in synergism with other factors, management can negatively impact co-nesters.…”

“…In the Beaver Archipelago of northern Lake Michigan, the abandonment of a colony on Gull Island and 42% fewer nesting pairs on Hat Island between 1997 and 2007 exemplify this decline (Cuthbert and Wires 2013). Records indicate that the colony on Hat Island has been active since at least the late 1800s (Reed 1965); such a dramatic reduction in breeding tern numbers could impact the long-term viability of the regional population (Shugart et al 1978). The reasons for the breeding population decline at important historical sites remains unclear, but factors could include unfavorable weather conditions, predators, changes in food supply and human disturbance (Shugart et al 1978;Cuthbert 1988;Cuthbert and Wires 1999).…”

“…Records indicate that the colony on Hat Island has been active since at least the late 1800s (Reed 1965); such a dramatic reduction in breeding tern numbers could impact the long-term viability of the regional population (Shugart et al 1978). The reasons for the breeding population decline at important historical sites remains unclear, but factors could include unfavorable weather conditions, predators, changes in food supply and human disturbance (Shugart et al 1978;Cuthbert 1988;Cuthbert and Wires 1999). These factors may not act independently but may together cause a synergistic effect reducing tern reproductive success.…”

Trends in Caspian Tern Nesting and Diet in San Francisco Bay: Conservation Implications for Terns and Salmonids

“…Low colony-site fidelity and frequent shifts among colony locations by Caspian Terns are associated with two primary factors: (1) the quality and quantity of nesting habitat and (2) disturbance and nest predation (Penland 1982;Shugart et al 1979;Cuthbert 1981;Gill and Mewaldt 1983;Antolos et al 2004). Inadequate nesting substrate or disturbance by various causes were documented at the majority of colony sites in SFBA, likely leading to the frequent shifts of nesting terns among colony locations, particularly in the South Bay.…”