Response of a remnant marmot population to habitat enhancement yields insights into marmot ecology

We evaluated the response of a remnant population of yellow-bellied marmots (Marmota flaviventris) to targeted habitat enhancement in an ecological system that had been degraded during ~100 years of intensive livestock management, including marmot eradication. We used capture-recapture data and a novel use of a multistate framework to evaluate geographic expansion of the marmot population pre- and post-habitat enhancement. We also estimated age-structured survival, reproduction, and sex ratios. The marmot population appeared to respond positively to new habitat opportunities created by habitat enhancement: the number of marmots captured increased from three marmots pre-habitat enhancement to 54 (28 adults and yearlings, 26 young) post-habitat enhancement at the end of the study. Marmots expanded geographically by transitioning into habitat-enhanced areas, and adult females occupied and reproduced in all habitat-enhanced areas. The sex ratio of the young population in 2019 was strongly female-biased, which may have been influenced by poor body condition of breeding females owing to unusually prolonged snow cover that year. Adult and yearling survival were within the range of that reported for colonial adults and yearlings in Colorado. Our results suggest that active habitat enhancement can assist in the recovery of marmot populations in systems where marmots historically existed.

Where to rewild? A conceptual framework to spatially optimize ecological function

Rewilding is an approach aiming at restoring ecosystems to a self-sustaining state by restoring ecological function through active reintroductions or passive management. Locations for most rewilding-through-reintroduction efforts today are selected based on the suitability of the habitat for the reintroduced species, often with little consideration of where the ecological function is most needed. We developed the Spatial Planning of Rewilding Effort (Spore) framework to identify priority locations for rewilding projects through simultaneous consideration of habitat suitability and provisioning of ecological function. We use the island of Guam as a case study for a potential rewilding project, as the island has functionally lost all native seed dispersers as a result of the invasive brown treesnake ( Boiga irregularis ). The Såli (Micronesian starling, Aplonis opaca ) is a good candidate for rewilding to restore ecological function, because it is an effective seed disperser with a localized remnant population. Using Spore, we identify three priority areas for the restoration of seed dispersal, each subdivided into management units. By recognizing the influence of landscape structure and the behaviour of the reintroduced species on the spatial pattern of the function provided by that species, this approach should lead to improved ecological outcomes.

THE LAST HURRAH: EXAMINING THE NATURE OF PERI-ABANDONMENT DEPOSITS AND ACTIVITIES AT CAHAL PECH, BELIZE

Archaeological investigations by the Belize Valley Archaeological Reconnaissance Project at Cahal Pech uncovered several Terminal Classic (a.d. 750–900) peri-abandonment deposits and activity areas at this Belize River Valley center. The deposits contained a diverse assemblage of cultural remains located above and between collapsed architecture, associated with evidence for burning activities. In the past, archaeologists have generally interpreted similar assemblages as “problematic deposits”—“de facto” refuse (garbage)—as associated with building termination and desecration, or as evidence for rapid abandonment during the violent destruction of these ancient cities. It is argued here that the microstratigraphic excavation and contextual analysis of these features provide limited support for these explanations. Alternatively, we suggest that the deposits are more likely associated with peri-abandonment rituals that were conducted by a reduced remnant population at Cahal Pech, or by small groups who continued to reside in the site's periphery during the last stages of the Terminal Classic period.

Evolution, natural history, and conservation of black-footed ferrets

Black-footed ferrets were reduced to a remnant population of 10 in 1985 due to diseases (plague, canine distemper), but successful captive breeding and releases have improved the prospects for ferret recovery. Comparisons between black-footed ferrets and Siberian polecats, close relatives that can interbreed and produce fertile offspring, allow the following evolutionary speculation. Predation on ferrets and polecats tends to narrow their niches and promote specialization due to requirements for escape habitats. In Asia, that influence is countered by the larger and more diverse area of steppe and alpine meadow habitats for polecats, and by plague which causes large variation in prey abundance. In North America, the selective pressure favoring specialization in ferrets on prairie dog prey and burrows had no strong counter-force before plague invaded. Plague is an immense challenge to black-footed ferret recovery, and several management tools including vaccines and vector control may be necessary to conserve the species.