1
|
Deep ocean drivers better explain habitat preferences of sperm whales Physeter macrocephalus than beaked whales in the Bay of Biscay. Sci Rep 2022; 12:9620. [PMID: 35688859 PMCID: PMC9187681 DOI: 10.1038/s41598-022-13546-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 05/25/2022] [Indexed: 11/09/2022] Open
Abstract
Species Distribution Models are commonly used with surface dynamic environmental variables as proxies for prey distribution to characterise marine top predator habitats. For oceanic species that spend lot of time at depth, surface variables might not be relevant to predict deep-dwelling prey distributions. We hypothesised that descriptors of deep-water layers would better predict the deep-diving cetacean distributions than surface variables. We combined static variables and dynamic variables integrated over different depth classes of the water column into Generalised Additive Models to predict the distribution of sperm whales Physeter macrocephalus and beaked whales Ziphiidae in the Bay of Biscay, eastern North Atlantic. We identified which variables best predicted their distribution. Although the highest densities of both taxa were predicted near the continental slope and canyons, the most important variables for beaked whales appeared to be static variables and surface to subsurface dynamic variables, while for sperm whales only surface and deep-water variables were selected. This could suggest differences in foraging strategies and in the prey targeted between the two taxa. Increasing the use of variables describing the deep-water layers would provide a better understanding of the oceanic species distribution and better assist in the planning of human activities in these habitats.
Collapse
|
2
|
Pereira JM, Ramos JA, Almeida N, Araújo PM, Ceia FR, Geraldes P, Marques AM, Matos DM, Rodrigues I, Dos Santos I, Paiva VH. Foraging costs drive within-colony spatial segregation in shearwaters from two contrasting environments in the North Atlantic Ocean. Oecologia 2022; 199:13-26. [PMID: 35044501 DOI: 10.1007/s00442-022-05109-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 12/07/2021] [Indexed: 11/24/2022]
Abstract
Foraging spatial segregation is frequent in central-place foragers during the breeding season, but very few studies have investigated foraging spatial segregation between adjacent sub-colonies. Here, we assessed for within-colony differences in the at-sea distribution, habitat use, trophic ecology and chick growth data of two Calonectris colonies differing in size, and breeding in two different environments in the North Atlantic Ocean. For this, we GPS tracked 52 Cory's shearwaters (Calonectris borealis) breeding in 2 small sub-colonies at Berlenga Island (Portugal) and 59 Cape Verde shearwaters (Calonectris edwardsii) breeding in 2 sub-colonies differing greatly in size at Raso Islet (Cabo Verde), over 2 consecutive breeding seasons (2017-2018), during chick-rearing. Cory's shearwaters from the two sub-colonies at Berlenga Island broadly overlapped in repeatedly used foraging patches close to the colony. In contrast, the foraging distribution of Cape Verde shearwaters was partially segregated in the colony surroundings, but overlapped at distant foraging areas off the west coast of Africa. Despite spatial segregation close to the colony, Cape Verde shearwaters from both sub-colonies departed in similar directions, foraged in similar habitats and exhibited mostly short trips within the archipelago of Cabo Verde. These results, corroborated with similar trophic ecology and chick growth rates between sub-colonies, support the idea that foraging spatial segregation in the colony surroundings was not likely driven by interference competition or directional bias. We suggest that high-quality prey patches are able to shape travel costs and foraging distribution of central-place foragers from neighbouring sub-colonies.
Collapse
Affiliation(s)
- Jorge M Pereira
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal. .,Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, UK.
| | - Jaime A Ramos
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Nathalie Almeida
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.,Biosfera Cabo Verde, Rua de Moçambique 28, Mindelo, Caixa Postal 233, São Vicente, Cabo Verde
| | - Pedro M Araújo
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.,CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, 4485-661, Vairão, Portugal
| | - Filipe R Ceia
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Pedro Geraldes
- SPEA-Sociedade Portuguesa para o Estudo das Aves, Av. Columbano Bordalo Pinheiro, 87, 3º Andar, 1070-062, Lisbon, Portugal
| | - Ana M Marques
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Diana M Matos
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Isabel Rodrigues
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.,Biosfera Cabo Verde, Rua de Moçambique 28, Mindelo, Caixa Postal 233, São Vicente, Cabo Verde
| | - Ivo Dos Santos
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| | - Vitor H Paiva
- Department of Life Sciences, MARE-Marine and Environmental Sciences Centre, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal
| |
Collapse
|