Observations of rapid colonization of constructed ponds by western toads (Bufo boreas) in Oregon, USA

  • Published source details Pearl C.A. & Bowerman J. (2006) Observations of rapid colonization of constructed ponds by western toads (Bufo boreas) in Oregon, USA. Western North American Naturalist, 66, 397–401.


This study is summarised as evidence for the following.

Action Category

Create ponds for toads

Action Link
Amphibian Conservation
  1. Create ponds for toads

    A replicated, before-and-after study in 1997–2004 of six created ponds in pine forest in Oregon, USA (Pearl & Bowerman 2006) found that western toads Bufo boreas established stable breeding populations in two of the ponds. Toads bred in all ponds in the first year after construction (within 2–9 months). At two sites large numbers of juveniles were recruited in the first year (1,000s–10,000s) and breeding continued in future years. However, breeding effort was small in the other four ponds, with less than three clutches and little or no recruitment of juveniles (<100 observed). With the exception of breeding in the second year at one of those ponds, there was no breeding in following years. Colonization events were estimated to be between three to over 20 pairs/pond. Ponds were created in 1997–2002. Five were <500 m2 in area and all were 0.1–4.8 km from natural breeding sites. Eggs, larvae and adults were monitored.


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