Draft Revised Recovery Plan for the Breeding Range of the Northern Great Plains Piping Plover

Home Browse Search

of Habitat Availability Section(page 62), we estimate that a habitat forming event likely occurred historically approximately every six-to-eight years, and the population would remain stable with a flood event(i.e., little to no habitat available during that year) occurring every four- to-eight years. Therefore, a 12 year period is long enough for several habitat forming events and a stationary population over time, albeit with fluctuations within that period as habitat forms and degrades. Stepping down the habitat goal: We recognize that the amount of habitat in specific areas will need to be stepped down further to provide local managers with goals specific to their area. We encourage managers within and between regions to start a dialogue to determine how much habitat each area can reasonably provide. We recognize that habitat is closely tied to population abundance, so areas with more habitat can be expected to support a larger percentage of the population. Approach to the habitat criterion: We used a model-based approach to determine the amount of breeding habitat necessary for a stable or increasing population in each region of the breeding range with a 95 percent confidence interval (i.e. less than 5 percent risk of extinction over the next 50 years). We used the best available information at the time of writing (2015) as input parameters for the model for life history traits(e.g.,juvenile and adult survival). Since we recognize that efforts to estimate the population may not be accurate (Shaffer et al. 2013), we included observation error in the model. As additional research is conducted and better information becomes available,the model can be updated in the future and the amount of habitat required for recovery may change accordingly. The Northern Great Plains Piping Plover Recovery Team will evaluate new information and update the model as they deem appropriate. The model is described in detail in Appendix 1B. Habitat needed per breeding pair: As discussed in the Habitat Acreage Requirements section(page 25)and in Appendix 1 B, modeling has found that 0.5 -0.67 ha(1.2-1.7 ac) is needed per breeding pair. From the information currently available, habitat should be available to support a density of no greater than 1.5-2 pairs/ha(0.58-0.61 pairs/acre)during each breeding season over the long term. So for each pair, 0.5-0.67 ha(1.2-1.7 acres)would be needed. Using the higher end of this range, 0.67 ha per pair should account for the fact that not all habitat identified remotely(the only feasible way of quantifying amount of habitat rangewide) will actually be suitable for piping plover breeding and foraging(see Prindiville-Gaines and Ryan 1988 and Anteau et al. 2012 for descriptions of piping plover habitat). Frequency of habitat availability: There are no historical data about annual habitat availability throughout the range. Therefore,we used proxy measures to estimate how often habitat would have been historically available. We 66 VOLUME!::Draft Revised Recovery Plan for the Breeding Range of the Northern Great Plains Piping Plover(Charadrius melodus)