Ten years of resident Canada goose damage management in a New Jersey tidal freshwater wetland

Abstract

ABSTRACTIntensive grazing by Atlantic Flyway Resident Population Canada geese (Branta canadensis) has been shown to dramatically reduce wild rice (Zizania aquatica) abundance in tidal freshwater marshes in the Mid‐Atlantic Region of the United States. From 2001 to 2010, I implemented an integrated damage management program (IDMP) during spring to abate Canada goose herbivory to wild rice in tidal freshwater marshes of the Maurice River, New Jersey, USA. The IDMP consisted of shooting, rendering goose nests unhatchable, and euthanizing molting geese. With implementation of an IDMP, the number of nests on the study area declined 70% over 10 years and the number of geese declined over time. Consequently, the amount of IDMP effort needed to sustain rice was reduced. Because the study area was a key nesting site for ospreys (Pandion haliaetus), which are state‐threatened species, there was concern that disturbance from IDMP activities could have a negative impact on osprey nesting or recruitment. The mean annual number of nesting ospreys doubled and the mean number of young fledged/nest was similar between years prior to and during implementation of the IDMP, suggesting that the IDMP did not have a negative impact on ospreys. Wetland managers should consider damage from excessive herbivory caused by non‐native, breeding waterfowl, such as resident Canada geese or mute swans (Cygnus olor), in their suite of wetland mitigation strategies. © 2013 The Wildlife Society.