Determinants of growth rates and mass of Canada geese goslings

• Published in: The Journal of Wildlife Management
• Main Authors: Conover, Michael R., Frank, Maureen G.
• Other Authors: Utah Agricultural Experiment Station
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2018
• Subjects: Arctic; Canada; Branta canadensis
• Online Access: http://dx.doi.org/10.1002/jwmg.21465; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjwmg.21465; https://onlinelibrary.wiley.com/doi/full/10.1002/jwmg.21465

ABSTRACT Fledgling mass is an important determinant of first‐year survival and recruitment into the breeding population for many Arctic‐nesting goose species. In turn, fledgling mass of these geese is influenced by hatch date and forage quality and quantity in the brood‐rearing area. Less is known about the determinants of growth rates and fledgling mass in temperate‐nesting geese. For 25 years, we examined near‐fledging mass, hatch dates, and growth rates of Canada geese ( Branta canadensis ) nesting in Connecticut, USA by tracking individually marked geese that wore neck collars or large plastic leg bands. Fledgling mass was influenced by sex (males were heavier), gosling age when weighed, and family type (fledglings raised in 2‐parent families were heavier than those raised in gang broods). Paternal nesting experience (years of prior nesting) influenced fledgling mass, probably because goslings with experienced fathers hatched earlier than goslings with inexperienced fathers. Among fledglings raised in gang broods, fledgling mass was positively correlated with the number of parents attending the brood and negatively correlated with the number of goslings within the brood. Gosling growth rates (daily gain in mass) were higher for males than females; goslings in 2‐parent families grew 2 g/day faster than those in gang broods. Late‐hatched goslings grew faster than goslings that hatched earlier. In gang broods, growth rates were positively correlated with the ratio of parents to goslings. Assessing goose sex ratios, Julian hatching dates, family types, and brood sizes will allow waterfowl managers in temperate regions to refine their goose population models. This, in turn, will allow waterfowl managers to determine more accurately what proportion of the populations can be safely harvested or how best to manage nuisance goose populations. © 2018 The Wildlife Society.