Identifying key habitats for the conservation of Chilean dolphins in the fjords of southern Chile

Abstract

ABSTRACT1. In the face of environmental degradation, animals with limited plasticity are likely to be the most vulnerable. 2. Habitat selection by the threatened, endemic Chilean dolphin (Cephalorhynchus eutropia) was investigated in the northern Patagonian fjords, an area of extraordinary biological productivity.3. Generalized additive models were undertaken to assess the ecological determinants of Chilean dolphin spatial distribution and habitat selection. Data were collected from dedicated fine-scale marine surveys conducted during the austral summer of 2007, 2008 and 2009 4. Modelling techniques provide strong support for Chilean dolphins aggregating in distinct hotspots, preferring shallow water, near rivers and in areas where the influence of tidal regime is greater.5. The preference for coastal shallow waters and river influenced habitats by Chilean dolphins puts them in direct conflict with a growing aquaculture industry and hydropower projects. The models predict areas of high densities of Chilean dolphins and excluding these areas from new developments would provide clear protection to the habitat most important to this poorly known endemic Chilean species.

Determining spatial use of the world's second largest humpback dolphin population: Implications for place‐based conservation and management

“…This study showed that humpback dolphins were not evenly distributed within the survey area, indicating that they do not use all their potential habitat range in equal intensity, similar to observations in other coastal dolphins (Bräger, Harraway, & Manly, ; Ingram & Rogan, ; Rayment et al, ; Viddi et al, ). The distribution patterns based on the GSD and DSD showed that humpback dolphins aggregated in several specific places within the survey area (Figure a–b).…”

“…For free‐ranging cetaceans, determination of important habitats is not only crucial to understanding several aspects of the ecology, dynamics and social structure of a population (Goetz et al, ; Ingram & Rogan, ), but also vital to effective place‐based conservation and management (Silva et al, ; Viddi et al, ). This study exemplifies that an appropriate survey design in terms of spatial and temporal consideration is needed in informing and developing place‐based management unit (Braulik et al, ; Cleguer, Grech, Garrigue, & Marsh, ; Filby, Stockin, & Scarpaci, ; Hartel et al, ).…”

“…For effective place‐based conservation management, it is urgent to develop a practicable plan with specific management targets (Cleguer et al, ; Silva et al, ). In particular, mitigation of anthropogenic pressures should be taken into consideration when protecting important dolphin habitats and developing the MPA network (Edgar et al, ; Smith, Frere, Kobryn, & Bejder, ; Viddi et al, ). Therefore, some conservation initiatives in relation to the main threats to humpback dolphins in the study area are proposed (Figure a−e; Liu, Dong, et al, ; Xu et al, , ; Zhou et al, ).…”

Integrating multiple data sources for assessing blue whale abundance and distribution in Chilean Northern Patagonia

“…Balaenoptera musculus are a local priority for conservation and marine spatial planning initiatives (Hucke‐Gaete et al., ; Outeiro et al., ) due to potential threats, including ship strikes, fishery and aquaculture net entanglement, poorly regulated whale watching activities and noise (Colpaert, Briones, Chiang, & Sayigh, ; Hoyt & Iñíguez, ; Hucke‐Gaete et al., , ; Van Waerebeek et al., ; Viddi, Harcourt, & Hucke‐Gaete, ). Thereby, reliable spatially explicit density maps for spatial planning and risk assessment are needed (Pennino et al., ; Redfern et al., ; Williams et al., ).…”

“…Balaenoptera musculus are a local priority for conservation and marine spatial planning initiatives (Hucke-Gaete et al, 2010;Outeiro et al, 2015) due to potential threats, including ship strikes, fishery and aquaculture net entanglement, poorly regulated whale watching activities and noise (Colpaert, Briones, Chiang, & Sayigh, 2016;Hoyt & Iñíguez, 2008;Hucke-Gaete et al, 2010Van Waerebeek et al, 2007;Viddi, Harcourt, & Hucke-Gaete, 2015).…”