IRC co-chair previews amphibian scoping proposal, flags gaps in fine-scale distribution and long‑term data

Jessica, an IRC co-chair, gave a brief scoping update on two amphibian research questions the committee will review more fully in July. She said Question 1 addresses multi-scale distributions and factors that influence occurrence at smaller spatial scales; Question 2 focuses on population trends for two torrent salamander species (Columbia and southern torrent species).

Jessica said existing literature defines broad geographic ranges for the five covered species but that "as you refine down to the watershed scale or even, more fine scale, that's pretty incompletely characterized for pretty much all of these species." She noted a lack of long-term standardized sampling and the frequent omission of imperfect detection in past techniques, which reduces reliability of some historical estimates. The co-chair added that little is known about genetic connectivity or population diversity for most species covered by the HCP.

The IRC is developing a menu of research options—ranging from relying on existing literature to targeted watershed- or within-watershed studies that could be paired to increase efficiency. The co-chairs said the group will provide a full draft scoping proposal to IRST at the committee's June 11 meeting and aims to deliver material in advance of the July 28 meeting so members have time to review.

The co-chairs highlighted that final budget estimates remain to be developed and that the scoping proposal will include a range of options with differing cost and data outcomes. The committee did not take a final action on the scoping questions at this meeting; members agreed to return to a deeper review at the July 28 session.

Next step: IRC will supply a full draft scoping proposal to IRST and committee members before the July meeting for detailed consideration.