Demographic consequences of translocation of overabundant Canada geese breeding in urban areas

Abstract

Translocation is a common tool for managing nuisance Canada geese (Branta canadensis) in urban areas across North America. However, no previous research has assessed how translocation affects survival and philopatry at donor and release sites. Such information is required for managers to decide if translocation is a suitable intervention to reach their management objectives. We used a joint multistate-dead recovery markrecapture analysis to retrospectively measure the effects of translocation on survival and fidelity of immature and adult Canada geese (n ¼ 2,946 marked individuals). Between 2009 and 2013, geese from Wascana Centre, an urban park in Regina, Saskatchewan, Canada, were subject to translocation to Cumberland Lake, a remote lake more than 400 km away. Survival varied between immature (mean annual survival ¼ 0.31, 95% CI ¼ 0.24-0.40) and adult (mean annual survival ¼ 0.72, 95% CI ¼ 0.69-0.75) geese, but translocation had no effect on survival probability. However, translocated immature geese had a lower mean probability of returning to Wascana (0.11, 95% CI ¼ 0.07-0.18) compared to adult geese (0.83, 95% CI ¼ 0.77-0.88). Translocation is unlikely to lead to a reduction in population density in our system given that translocation does not influence survival and adults return at high rates after being moved. If translocation is the only management option available, then the focus should be on immature geese. If translocation is used as a management option to minimize the number of geese that would need to be lethally removed, then managers should translocate immature geese and cull adult geese to reach management objectives. Ó 2017 The Wildlife Society.

Human-modified biogeographic patterns and conservation in game birds: The dilemma of the black francolin (Francolinus francolinus, Phasianidae) in Pakistan

“…At the moment no such data are available for the black francolin, nor is possible to rule out a priori the possibility that this unintentional genetic mixing might play some sort of genetic rescue effect on declining populations [ 88 ]. Nevertheless, translocations of philopatric avian species were showed to be successful on condition that mostly immatures are released [ 89 – 90 ], this not being the case of the present study. On the other hand, the heterozygote deficiency we detected could be possibly indicative of ongoing drift and, as such, suggest that either (i) translocations are hastening the decline by erasing genetic diversity or (ii) that no genetic rescue effect is occurring at all and that (iii), if any, it is overridden by a likely demographic decrease.…”

Translocation, survival, and recovery of Kansas‐banded Canada geese

“…Translocating adult and juvenile geese could reduce nuisance issues if most individuals do not return to their original capture location (Surrendi 1970, Fritzell and Soulliere 2004, Sanders and Dooley 2014, Flockhart and Clarke 2017. Translocating nuisance geese >150 km to areas with legal harvest successfully reduced local nuisance issues and increased hunter harvest in New York (Smith et al 1999, Holevinski et al 2006.…”

Banded Canada Goose Resightings in Wascana Park, Regina, Saskatchewan

“…1 Annual survival rates of adult Canada geese range from 46 per cent in the Atlantic Flyway to 72 per cent over a four-year period in Regina, Saskatchewan. 2,3 Furthermore, urban geese typically have higher survival rates as compared to rural geese and tend to return to the same areas year after year. 4 There has been a long history of banding Canada geese in Regina.…”