Cetacean-habitat modeling, although still in the early stages of development, represents a potentially powerful tool for predicting cetacean distributions and understanding the ecological processes determining these distributions. Marine ecosystems vary temporally on diel to decadal scales and spatially on scales from several meters to 1000s of kilometers. Many cetacean species are wideranging and respond to this variability by changes in distribution patterns. Cetacean-habitat models have already been used to incorporate this variability into management applications, including improvement of abundance estimates, development of marine protected areas, and understanding cetacean-fisheries interactions. We present a review of the development of cetacean-habitat models, organized according to the primary steps involved in the modeling process. Topics covered include purposes for which cetacean-habitat models are developed, scale issues in marine ecosystems, cetacean and habitat data collection, descriptive and statistical modeling techniques, model selection, and model evaluation. To date, descriptive statistical techniques have been used to explore cetacean-habitat relationships for selected species in specific areas; the numbers of species and geographic areas examined using computationally intensive statistic modeling techniques are considerably less, and the development of models to test specific hypotheses about the ecological processes determining cetacean distributions has just begun. Future directions in cetacean-habitat modeling span a wide range of possibilities, from development of basic modeling techniques to addressing important ecological questions.

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Primary sources of mortality and serious injury to endangered North Atlantic right whales Eubalaena glacialis are vessel strikes and entanglement in fishing gear. All management plans depend on knowing when and where right whales are likely to be present. We tested the feasibility of a system designed to predict potential right whale habitat on a weekly time scale. The system paired right whale occurrence records with a collection of data layers including: results from a coupled biological−physical model of Calanus finmarchicus (the primary prey of right whales), satellite-derived sea surface temperature and chlorophyll, and bathymetry. Using these data, we trained seasonal habitat models and projected them onto environmental data for each 8 d period from January to June, 2002 to 2006. Two hypotheses were tested: (1) that right whale environmental preferences change from season to season and (2) that modeled prey concentration is an important predictor of the distribution of right whales. To test H 1 , we trained, tested, and compared models for 3 time periods: winter, spring, and winter and spring combined. To test H 2 , we trained and tested models with and without C. finmarchicus. Predictions of habitat suitability were highly dynamic within and across years. Our results support the hypothesis that right whale environmental preferences change between winter and spring. The inclusion of modeled C. finmarchicus abundance improved the accuracy of habitat suitability predictions.

Despite many years of study and protection, the North Atlantic right whale (Eubalaena glacialis) remains on the brink of extinction. There is a crucial gap in our understanding of their habitat use in the migratory corridor along the eastern seaboard of the United States. Here, we characterize habitat suitability in migrating right whales in relation to depth, distance to shore, and the recently enacted ship speed regulations near major ports. We find that the range of suitable habitat exceeds previous estimates and that, as compared with the enacted 20 nautical mile buffer, the originally proposed 30 nautical mile buffer would protect more habitat for this critically endangered species.Résumé : Malgré de nombreuses années d'étude et de protection, la baleine franche du nord (Eubalaena glacialis) de l'Atlantique Nord demeure au bord de l'extinction. Il y a une faille essentielle dans notre compréhension de leur utilisation de l'habitat dans le corridor de migration le long de la côte est des É tats-Unis. Nous caractérisons ici la convenance des habitats pour les baleines franches en migration en relation avec la profondeur, la distance de la rive et la réglementation ré-cemment en vigueur sur la vitesse des navires près des ports principaux. Nous trouvons que la gamme d'habitats adéquats dépasse les estimations précédentes et que, par comparaison à la zone tampon de 20 milles marins présentement en vigueur, la zone tampon de 30 milles marins proposée à l'origine protégerait plus d'habitats pour cette espèce sérieusement menacée de disparition.[Traduit par la Rédaction]

Hypoxic bottom waters (dissolved oxygen ≤2.0 mg l -1 ) in the northwestern Gulf of Mexico are largely due to nutrient loading from the Mississippi-Atchafalaya watershed. Loss of benthic habitat has been documented in bottom trawl surveys, but little is known about the effect of hypoxia on the vertical distribution of fish biomass. To investigate these effects, we used a 120 kHz split-beam echosounder to compare the vertical distribution of fish biomass at stations with hypoxic bottom waters to those with normoxic bottom waters. We also used paired mongoose and flat trawls to assess species composition, and a CTD to measure physical characteristics of the water column. Atlantic croaker Micropogonias undulatus, Atlantic bumper Chloroscombrus chrysurus, and anchovies (Anchoa spp.) comprised 92% (by number) of fish sampled. Dissolved oxygen, time of day, and depth within the water column were the major factors explaining variation in acoustic biomass. Stations inside and outside of the hypoxic zone had similar overall density but differed in vertical distribution. Hypoxic stations had greater biomass in the upper 7 m of the water column and much less biomass below 13 m compared to normoxic stations, consistent with aggregation of organisms above the bottom hypoxic layer. We did not find evidence of strong aggregation at the hypoxic edge throughout the entire water column. While the pelagic habitat is not directly impacted by lowoxygenated bottom water, hypoxia can induce vertical or horizontal displacement of fish mediating potential indirect bioenergetic or trophic interactions.

We describe the development of a comprehensive set of marine mammal habitat models for the US east coast and Gulf of Mexico and their delivery through an online mapping portal. Drawing from datasets in the online OBIS-SEAMAP geo-database, we integrated surveys conducted by ship (n = 36) and aircraft (n = 16), weighting a generalized additive model (GAM) by minutes surveyed within space−time grid cells to harmonize effort between the 2 survey platforms. For each of 16 cetacean species guilds, we predicted the probability of occurrence from static environmental variables (water depth, distance to shore, distance to continental shelf break) and time-varying conditions (monthly sea surface temperature). To generate maps of presence versus absence, receiver operator characteristic (ROC) curves were used to define the optimal threshold that minimizes false positive and false negative error rates. We integrated model outputs, including tables (species in guilds, input surveys) and plots (fit of environmental variables, ROC curve), into an online spatial decision support system (SDSS), allowing for easy navigation of models by taxon, region, season, and data provider. Users can define regions of interest and extract statistical summaries of the model for that region. The SDSS also displays density models from other providers and regions (e.g. Pacific Ocean). This versatile, easy-to-use online system enables the application of these habitat models to real-world conservation and management issues. Finally, we discuss the ecological relevance of these model outputs and identify key data gaps across species, regions, and seasons. KEY WORDS: Species distribution model • Habitat • Cetacea • Generalized additive model • Spatial decision support system • Atlantic Ocean • Gulf of Mexico Resale or republication not permitted without written consent of the publisher Contribution to the Theme Section 'Beyond marine mammal habitat modeling'

Simple SummaryThis opinion piece explores how implementing a species royalty for the use of animal symbolism in affluent cultural economies could revolutionise conservation funding. A revenue revolution of this scale is urgently necessary to confront the sixth mass extinction that the planet is now facing. But such a revolution can only occur if the approach to conservation now evolves quickly across disciplines, continents, cultures and economies. This piece is a call to action for research-, culture-, and business-communities to implement a new ethical phase in economic policy that recognises the global cultural debt to the world’s most charismatic wildlife species.AbstractOn 2 July 2015, the killing of a lion nicknamed “Cecil” prompted the largest global reaction in the history of wildlife conservation. In response to this, it is propitious to consider the ways in which this moment can be developed into a financial movement to transform the conservation of species such as the lion that hold cultural significance and sentiment but whose numbers in the wild are dwindling dangerously. This provocative piece explores how a species royalty could be used effectively by drawing revenue from the heavy symbolic use of charismatic animals in affluent economies. This would, in turn, reduce strain on limited government funds in threatened animals’ native homelands. Three potential areas of lucrative animal symbolism—fashion, sports mascots, and national animals—provide examples of the kind of revenue that could be created from a species royalty. These examples also demonstrate how this royalty could prove to be a desirable means by which both corporations and consumers could positively develop their desired selves while simultaneously contributing to a relevant and urgent cause. These examples intend to ignite a multi-disciplinary conversation on the global cultural economy’s use of endangered species symbols. An overhaul in perspective and practice is needed because time is running out for much of the wildlife and their ecosystems that embellish products and embody anthropocentric business identities.

The understanding of a species' niche is fundamental to the concept of ecology, yet relatively little work has been done on niches in pelagic marine mammal communities. Data collection on the distribution and abundance of marine mammals is costly, time consuming and complicated by logistical difficulties. Here we take advantage of a data archive comprising many different datasets on the distribution and abundance of cetaceans from Nova Scotia through the Gulf of Mexico in an effort to uncover community structure at large spatial scales (1000s of km). We constructed a multivariate ordination of the species data, tested for group structure that might exist within the ordination space, and determined how these groups might differ in environmental space. We examined 3 biogeographic regions: the oceanic waters north and south of Cape Hatteras, NC, and the Gulf of Mexico. North of Hatteras, we found 2 main groups split along a temperature and chlorophyll gradient, with most piscivores being found in cooler, more productive waters of the continental shelf, and most teuthivores being found farther offshore in warmer, less productive waters at the shelf break (200 m isobath). South of Hatteras, we found 3 groups, with the largest group being in warmer, lower chlorophyll waters that are closest to shore. In the Gulf of Mexico, we found 7 groups arrayed along a bottom depth gradient. We also tested the effect of taxonomically lumping different beaked whale species on ordination results. Results showed that when beaked whales were identified to the species level, they clustered out into distinct niches that are separate from those of other Odontocete groups. These results add to an increasing understanding of wildlife habitat associations and niche partitionings in the community structure of pelagic species, and provide important baseline information for future population monitoring efforts. KEY WORDS: Cetaceans · Group contrast Mantel test · Nonmetric dimensional scaling · Multivariate ordination · Northwest Atlantic OceanResale or republication not permitted without written consent of the publisher