Differential resilience of Amazonian otters along the Rio Negro in the aftermath of the 20th century international fur trade

Abstract

Commercial hunting for the international trade in animal hides in the 20th century decimated many populations of aquatic wildlife in Amazonia. However, impacts varied significantly between different species and regions, depending upon hunting intensity, accessibility of habitat, and the inherent resilience of various species and their habitats. We investigated the differential responses of two Amazonian Mustelid species, the neotropical otter and giant otter, to commercial hunting pressure along the upper Rio Negro in Brazil, and examined historical factors that influenced spatial and temporal variation in commercial exploitation. We analyzed previously unanalyzed data from historical records of hide shipments to track changes in hide sales and prices for the two species in the late 20th century. We also gathered oral histories from older Baniwa people who had witnessed or participated in commercial otter hunting. These complimentary data sources reveal how intrinsic biological and social characteristics of the two otter species interacted with market forces and regional history. Whereas giant otter populations were driven to local or regional extinction during the late 20th century by commercial hunting, neotropical otters persisted. In recent decades, giant otter populations have returned to some parts of the upper Rio Negro, a development which local people welcome as part of a generalized recovery of the ecosystems in their territory as a result of the banning of animal pelt exports and indigenous land demarcation. This paper expands the scope of the field historical ecology and reflects on the role of local knowledge in biodiversity conservation.

Conservation of Amazonian aquatic mammals

“…Otters were also hunted intensively in the Amazon for the international pelt trade until the mid‐1970s, with hundreds of thousands of pelts exported from the Brazilian Amazon (Antunes et al, 2016). In just a few decades, hunting is thought to have caused many local and regional collapses of P. brasiliensis populations (Antunes et al, 2016; Pimenta, Antunes, Barnett, Macedo, & Shepard, 2018). Owing to their biology and behaviour, P. brasiliensis is more susceptible to persecution by fishers and hunters than L. longicaudis , whose populations persisted at low densities during this period (Pimenta, Antunes, et al, 2018).…”

“…In just a few decades, hunting is thought to have caused many local and regional collapses of P. brasiliensis populations (Antunes et al, 2016;Pimenta, Antunes, Barnett, Macedo, & Shepard, 2018). Owing to their biology and behaviour, P. brasiliensis is more susceptible to persecution by fishers and hunters than L. longicaudis, whose populations persisted at low densities during this period (Pimenta, Antunes, et al, 2018). Since international trade restrictions and conservationist efforts were implemented in the mid-1970s, P. brasiliensis populations have shown signs of recovery in many parts of their range (Lima, Marmontel, & Bernard, 2014b;Pimenta, Gonçalves, Shepard, Macedo, & Barnett, 2018;Recharte & Bodmer, 2009), although in some regions this species is still considered extinct or nearly so, or with declining population trends (Groenendijk et al, 2015).…”

High‐resolution drone imagery reveals drivers of fine‐scale giant otter habitat selection in the land‐water interface

“…We implemented a multi-scale approach to assess the most appropriate response scale for analysis of habitat variables (Macdonald et al, 2019;Pimenta, Gonçalves, et al, 2018), subsequently specified as predictors in a resource selection function (RSF; Manly et al, 2002) which examined used and available habitat for giant otters within oxbow lakes. All areas inside lakes were considered available habitat for giant otters, because they constitute part of group territories (Groenendijk, Duplaix, et al, 2015).…”

“…We studied giant otter family groups in oxbow lakes of Madre de Dios, a biodiversity hotspot in Peru. Madre de Dios province holds several PAs, where giant otter populations are slowly recovering from severe recent declines caused predominantly by commercial hunting (Groenendijk et al, 2014; Pimenta, Antunes, et al, 2018). However, in recent years the region experienced expansion of artisanal small‐scale gold mining (hereafter gold mining), mainly along watersheds outside PAs (Asner et al, 2013; Caballero‐Espejo et al, 2018).…”

Historical Ecology in Brazil: A Systematic Mapping of Scientific Articles (1998–2021)

“…Out of the whole universe of articles, 23 focused on a particular species. The species that figured as the central theme of investigation are a protozoan species from the genus Plasmodium as an agent of malaria in humans and other primates [71]; fish species such as largetooth sawfish (Pristis pristis) and goliath grouper (Epinephelus itajara) [116], and lane snapper (Lutjanus synagris) [106]; the neotropical otter (Lontra longicaudis) and the giant otter (Pteronura brasiliensis) [136]. The remainder of the 19 articles is regarding plant species.…”