Distribution of breeding humpback whale habitats and overlap with cumulative anthropogenic impacts in the Eastern Tropical Atlantic

• Published in: Diversity & distributions Vol. 26; no. 5; pp. 549 - 564
• Main Authors: Chou, Emily, Kershaw, Francine, Maxwell, Sara M., Collins, Tim, Strindberg, Samantha, Rosenbaum, Howard C.
• Format: Journal Article
• Language: English
• Published: Oxford Wiley 01.05.2020; John Wiley & Sons, Inc
• Subjects: Animal behavior; anthropogenic activity; Anthropogenic factors; Aquatic mammals; Behavior; BIODIVERSITY RESEARCH; Breeding; breeding habitat; Climate change; Coastal ecology; Coastal waters; cumulative impacts; Equatorial regions; Geographical distribution; Gulf of Guinea; Habitat utilization; Habitats; Human influences; humpback whale; Impact analysis; Maxent; Megaptera; Population; Reproductive behavior; Sea surface temperature; species distribution models; Telemetry; Whales; Whales & whaling; Wind speed; Gabon; Southern Hemisphere
• ISSN: 1366-9516; 1472-4642
• DOI: 10.1111/ddi.13033

Aim Species distribution modelling is a useful tool for determining important habitats. By accounting for specific animal behaviour in the model, it is possible to identify finer‐scale patterns of habitat use. Together with spatially explicit data on anthropogenic activities, models can be used to assess human impacts and inform conservation management. This study used observations of breeding behaviour to identify fine‐scale breeding habitats of humpback whales (Megaptera novaeangliae), as well as potential overlap of these habitats with cumulative anthropogenic impacts. Location Eastern Tropical Atlantic, West Africa. Methods Maxent was used to model humpback distribution using pertinent environmental predictors and an integrated dataset of humpback whale occurrences filtered for breeding‐specific behaviours. In conjunction with multiple anthropogenic activities, a subsequent cumulative utilization and impact analysis assessed the degree of overlap between predicted breeding habitat and potential anthropogenic impacts. Results Greatest habitat suitability occurred in warm coastal waters of Gabon, and other highly suitable areas occurred off Equatorial Guinea (Bioko Island), Cameroon and Angola. Sea surface temperature and height contributed most to the model. Highest overlap between humpback whales and potential impacts from anthropogenic activities occurred off Gabon, Equatorial Guinea (Bioko Island), Cameroon and Angola. Impacts associated with oil and gas development (where oil and gas platforms serve as an indicator for industry activity) appeared to contribute most to potential cumulative impact. Main Conclusions Depth and sea surface temperature of predicted breeding habitats were consistent with previous studies. However, lesser known characteristics such as sea surface height and wind speed, resulting in potentially more sheltered areas for breeding whales, may also be important in delineating finer‐scale habitat suitability. Identified areas of high potential cumulative impact occurred within exclusive economic zones of multiple countries and likely represent the minimum level of impact to humpback whales in the region, highlighting the need for additional research and effective management throughout the area.