Augmentations are used frequently to restore populations of conservation concern. Carnivores, in particular, are often targeted for augmentations, yet quantitative assessments of these efforts are rare. In Wisconsin, USA, American martens were reintroduced and subsequently augmented, yet remain state endangered. To evaluate this restoration effort, we sampled martens before and after augmentation, used genetic mark-recapture and parentage analyses to quantify stage-specific vital rates for each step of the augmentation, and assessed demographic viability with and without augmentation. Surprisingly, augmentation provided minimal genetic and demographic contributions, and persistence was instead driven by intrinsic population attributes such as recruitment. Our findings question augmentation as a primary restoration strategy for carnivores, and we urge conservation practitioners to focus on identifying and enhancing limiting population processes such as immigration and juvenile survival prior to using costly and controversial measures like augmentation.

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Reintroductions are frequently conducted to restore carnivore populations, though many fail despite following best management practices. Although demographic approaches are increasingly used to assess reintroduced populations, immigration is often overlooked in reintroduction planning and assessment. American martens (Martes americana) were reintroduced to 2 sites in Wisconsin, the Nicolet and Chequamegon national forests, which have anecdotally experienced differential population recovery. Via non‐invasive sampling and a mark‐recapture framework, we explored the possible mechanisms behind the divergent trajectories of the Nicolet National Forest (Nicolet) population, which appears to be recovering, and the Chequamegon National Forest (Chequamegon) population, which appears to be declining toward extinction. We tested for site‐level differences in survival, estimated population size, and calculated immigration rates based on simulations of the original reintroductions to the Nicolet. We then projected each population forward, both with and without our estimated immigration rate. We calculated a current population size of 66 female martens in the Nicolet, and estimated that the reintroduced population would have reached this size if supplemented by 1 female immigrant per year. We simulated future populations with the estimate of 1 female immigrant per year; this sustained level of immigration to the Nicolet reduced the probability of extinction to <1% over the next 100 years. When we applied the same rate of immigration to the starting population of 22 female martens in the Chequamegon, extinction probabilities were reduced by approximately 30%. Despite similarities between the 2 reintroduction sites, we propose that the differential population recovery was primarily due to modest rates of immigration to the Nicolet and the relative isolation of the Chequamegon population. Martens in the Chequamegon have been projected to go extinct in the foreseeable future, yet increasing connectivity with the Nicolet or Upper Peninsula of Michigan could improve persistence. Our results illustrate the effect of modest immigration on reintroduction success and the importance of planning for connectivity across reintroduction sites. © 2019 The Wildlife Society.

The northern goshawk (Accipiter gentilis atricapillus) is a woodland raptor that uses a variety of forest types for nesting across its breeding range, but strongly depends on older forests with large trees and open understories. Goshawks may select nesting locations by maximizing the convergence of nesting and foraging habitats. Insights into goshawk responses to heterogeneous landscapes can be gained by examining the location of active nest sites through time and at multiple spatial scales. We examined the landscape-scale forest conditions that influenced the probability of active goshawk nests in the United States Forest Service, Chequamegon-Nicolet National Forest (CNNF) in northern Wisconsin. We used goshawk nest survey and monitoring data from 1997 to 2006 to determine the probability of an active nest site over time in relation to forest composition and road density at 3 scales (200-m, 500-m, and 1,000-m radii). Goshawk nests were located primarily in upland hardwood (64%), conifer (23%), and older aspen-birch (!26 yrs old; 11%) habitat cover types. We used Bayesian temporal autoregressive models of nest locations across multiple spatial scales to analyze these data. The probability of active goshawk nest occurrence increased with increasing conifer cover (1,000 m) and decreased with increasing cover of older aspen-birch and density of primary roads (500 m). In addition, lesser proportions of older aspen-birch at intermediate scales around goshawk nests had a stronger effect on the probability of a nest being active than conifer and primary roads. Thus, the ratio of conifer cover (within 1,000 m) to older aspen-birch cover (within 500 m) in landscapes surrounding nest sites was the key driver in predicting the probability of an active nest site. This finding can be used by forest managers to help sustain the active status of a goshawk nesting area through time (i.e., annually), and foster goshawk nesting activity in areas where active nesting is not currently occurring. ß Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

To better understand the genetic outcomes of the translocation and inform future management strategies, we quantified the genetic diversity of translocated individuals, and then simulated how genetic diversity would erode over time under different scenarios: single translocation, additional augmentations, and rates of natural immigration. For such isolated populations, which are typical for many translocations, future augmentations and maintaining connectivity through the planning of a recovery network is critical to meet the stated goals of increasing genetic diversity and population persistence. In particular, we argue that an a priori assessment will improve translocation practices that define goals, feasibility, and adaptive strategies to maintain genetic diversity of at‐risk populations.