1
|
Taboada FG, Chust G, Santos Mocoroa M, Aldanondo N, Fontán A, Cotano U, Álvarez P, Erauskin-Extramiana M, Irigoien X, Fernandes-Salvador JA, Boyra G, Uriarte A, Ibaibarriaga L. Shrinking body size of European anchovy in the Bay of Biscay. GLOBAL CHANGE BIOLOGY 2024; 30:e17047. [PMID: 38273534 DOI: 10.1111/gcb.17047] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 10/21/2023] [Accepted: 10/31/2023] [Indexed: 01/27/2024]
Abstract
Decreased body size is often cited as a major response to ocean warming. Available evidence, however, questions the actual emergence of shrinking trends and the prevalence of temperature-driven changes in size over alternative drivers. In marine fish, changes in food availability or fluctuations in abundance, including those due to size-selective fishing, provide compelling mechanisms to explain changes in body size. Here, based on three decades of scientific survey data (1990-2021), we report a decline in the average body size-length and weight-of anchovy, Engraulis encrasicolus L., in the Bay of Biscay. Shrinking was evident in all age classes, from juveniles to adults. Allometric adjustment indicated slightly more pronounced declines in weight than in total length, which is consistent with a change toward a slender body shape. Trends in adult weight were nonlinear, with rates accelerating to an average decline of up to 25% decade-1 during the last two decades. We found a strong association between higher anchovy abundance and reduced juvenile size. The effect of density dependence was less clear later in life, and temperature became the best predictor of declines in adult size. Theoretical analyses based on a strategic model further suggested that observed patterns are consistent with a simultaneous, opposing effect of rising temperatures on accelerating early growth and decreasing adult size as predicted by the temperature-size rule. Macroecological assessment of ecogeographical-Bergmann's and James'-rules in anchovy size suggested that the observed decline largely exceeds intraspecific variation and might be the result of selection. Limitations inherent in the observational nature of the study recommend caution and a continued assessment and exploration of alternative drivers. Additional evidence of a climate-driven regime shift in the region suggests, however, that shrinking anchovy sizes may signal a long-lasting change in the structure and functioning of the Bay of Biscay ecosystem.
Collapse
Affiliation(s)
- Fernando G Taboada
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Guillem Chust
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - María Santos Mocoroa
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Naroa Aldanondo
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Almudena Fontán
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Unai Cotano
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Paula Álvarez
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | | | - Xabier Irigoien
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | | | - Guillermo Boyra
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Andrés Uriarte
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| | - Leire Ibaibarriaga
- AZTI Marine Research, Basque Research and Technology Alliance (BRTA), Sukarrieta, Spain
| |
Collapse
|
2
|
Payet SD, Pratchett MS, Saenz‐Agudelo P, Berumen ML, DiBattista JD, Harrison HB. Demographic histories shape population genomics of the common coral grouper ( Plectropomus leopardus). Evol Appl 2022; 15:1221-1235. [PMID: 36051464 PMCID: PMC9423088 DOI: 10.1111/eva.13450] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 06/02/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022] Open
Abstract
Many coral reef fishes display remarkable genetic and phenotypic variation across their geographic ranges. Understanding how historical and contemporary processes have shaped these patterns remains a focal question in evolutionary biology since they reveal how diversity is generated and how it may respond to future environmental change. Here, we compare the population genomics and demographic histories of a commercially and ecologically important coral reef fish, the common coral grouper (Plectropomus leopardus [Lacépède 1802]), across two adjoining regions (the Great Barrier Reef; GBR, and the Coral Sea, Australia) spanning approximately 14 degrees of latitude and 9 degrees of longitude. We analysed 4548 single nucleotide polymorphism (SNP) markers across 11 sites and show that genetic connectivity between regions is low, despite their relative proximity (~100 km) and an absence of any obvious geographic barrier. Inferred demographic histories using 10,479 markers suggest that the Coral Sea population was founded by a small number of GBR individuals and that divergence occurred ~190 kya under a model of isolation with asymmetric migration. We detected population expansions in both regions, but estimates of contemporary effective population sizes were approximately 50% smaller in Coral Sea sites, which also had lower genetic diversity. Our results suggest that P. leopardus in the Coral Sea have experienced a long period of isolation that precedes the recent glacial period (~10-120 kya) and may be vulnerable to localized disturbances due to their relative reliance on local larval replenishment. While it is difficult to determine the underlying events that led to the divergence of the Coral Sea and GBR lineages, we show that even geographically proximate populations of a widely dispersed coral reef fish can have vastly different evolutionary histories.
Collapse
Affiliation(s)
- Samuel D. Payet
- Australian Research Council Centre of Excellence for Coral Reef StudiesJames Cook UniversityTownsvilleQueenslandAustralia
| | - Morgan S. Pratchett
- Australian Research Council Centre of Excellence for Coral Reef StudiesJames Cook UniversityTownsvilleQueenslandAustralia
| | - Pablo Saenz‐Agudelo
- Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile
| | - Michael L. Berumen
- Division of Biological and Environmental Science and Engineering, Red Sea Research CenterKing Abdullah University of Science and TechnologyThuwalSaudi Arabia
| | - Joseph D. DiBattista
- Australian Museum Research Institute, Australian MuseumSydneyNew South WalesAustralia
| | - Hugo B. Harrison
- Australian Research Council Centre of Excellence for Coral Reef StudiesJames Cook UniversityTownsvilleQueenslandAustralia
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
| |
Collapse
|