Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands
Interactions between seals and commercial fisheries can pose a significant threat to the conservation status of seal populations. In the Falkland Islands, home to over 50 % of the global South American fur seal (SAFS) population, there has been a dramatic (∼ 900 %) increase in the number of SAFS-fis...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2023-10-01
|
| Series: | Global Ecology and Conservation |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2351989423002500 |
| _version_ | 1797676297320660992 |
|---|---|
| author | Javed Riaz Rachael A. Orben Kayleigh A. Jones Megan Shapiro Andreas Winter Paul Brickle Alastair M.M. Baylis |
| author_facet | Javed Riaz Rachael A. Orben Kayleigh A. Jones Megan Shapiro Andreas Winter Paul Brickle Alastair M.M. Baylis |
| author_sort | Javed Riaz |
| collection | DOAJ |
| description | Interactions between seals and commercial fisheries can pose a significant threat to the conservation status of seal populations. In the Falkland Islands, home to over 50 % of the global South American fur seal (SAFS) population, there has been a dramatic (∼ 900 %) increase in the number of SAFS-fishery interactions in recent years. However, significant knowledge gaps regarding SAFS spatiotemporal foraging behaviour and habitat use hinders our capacity to assess the ecological mechanisms underpinning these interactions. In this study, we investigate the spatial overlap between SAFS foraging effort and commercial squid and finfish trawl fisheries in the Falkland Island Exclusive Economic Zone (EEZ). By spatially integrating two years of SAFS horizontal and vertical movement data with contemporaneous trawl-by-trawl information from the Falkland Islands fishing fleet, we examine whether SAFS concentrate their foraging effort in areas associated with greater squid and finfish catch quantities. Our findings reveal a marked spatial overlap between SAFS foraging effort and commercial trawling activity within the Falkland Islands EEZ, particularly in areas associated with Patagonian longfin squid (Doryteuthis gahi) and common hake (Merluccius hubbsi). Across the various metrics of foraging effort (summarised dive activity) examined, we found SAFS performed a greater number of dives, travelled greater vertical distances and performed deeper dives in intensively fished areas. These results suggest SAFS forage in the same habitats targeted by commercial squid and finfish fisheries, where they compete for demersal resources by performing a high frequency of deep dives. The implications of our findings are discussed within the broader context of local prey-field dynamics and fisheries-management. This study represents one of the most comprehensive investigations of SAFS movement ecology and advances our understanding of seal-fishery interactions in the Falkland Islands EEZ – a topic of increasing management concern. Importantly, this work can support conservation efforts for this globally significant SAFS population and contribute to long-term marine management objectives of the Falkland Islands fishery. |
| first_indexed | 2024-03-11T22:25:56Z |
| format | Article |
| id | doaj.art-7dfef72ca0f945e99d3a479782747bdf |
| institution | Directory Open Access Journal |
| issn | 2351-9894 |
| language | English |
| last_indexed | 2024-03-11T22:25:56Z |
| publishDate | 2023-10-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Global Ecology and Conservation |
| spelling | doaj.art-7dfef72ca0f945e99d3a479782747bdf2023-09-24T05:15:34ZengElsevierGlobal Ecology and Conservation2351-98942023-10-0146e02615Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland IslandsJaved Riaz0Rachael A. Orben1Kayleigh A. Jones2Megan Shapiro3Andreas Winter4Paul Brickle5Alastair M.M. Baylis6South Atlantic Environmental Research Institute, Stanley FIQQ 1ZZ, Falkland Islands; Corresponding author.Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Hatfield Marine Science Center, Newport, OR 97365, USABritish Antarctic Survey, High Cross, Madingley Rd, Cambridge CB3 0ET, UK; College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UKSouth Atlantic Environmental Research Institute, Stanley FIQQ 1ZZ, Falkland IslandsFisheries Department, Falkland Islands Government, Bypass Road, Stanley FIQQ 1ZZ, Falkland IslandsSouth Atlantic Environmental Research Institute, Stanley FIQQ 1ZZ, Falkland Islands; School of Biological Sciences (Zoology), University of Aberdeen, Aberdeen, Scotland AB24 2TZ, UKSouth Atlantic Environmental Research Institute, Stanley FIQQ 1ZZ, Falkland IslandsInteractions between seals and commercial fisheries can pose a significant threat to the conservation status of seal populations. In the Falkland Islands, home to over 50 % of the global South American fur seal (SAFS) population, there has been a dramatic (∼ 900 %) increase in the number of SAFS-fishery interactions in recent years. However, significant knowledge gaps regarding SAFS spatiotemporal foraging behaviour and habitat use hinders our capacity to assess the ecological mechanisms underpinning these interactions. In this study, we investigate the spatial overlap between SAFS foraging effort and commercial squid and finfish trawl fisheries in the Falkland Island Exclusive Economic Zone (EEZ). By spatially integrating two years of SAFS horizontal and vertical movement data with contemporaneous trawl-by-trawl information from the Falkland Islands fishing fleet, we examine whether SAFS concentrate their foraging effort in areas associated with greater squid and finfish catch quantities. Our findings reveal a marked spatial overlap between SAFS foraging effort and commercial trawling activity within the Falkland Islands EEZ, particularly in areas associated with Patagonian longfin squid (Doryteuthis gahi) and common hake (Merluccius hubbsi). Across the various metrics of foraging effort (summarised dive activity) examined, we found SAFS performed a greater number of dives, travelled greater vertical distances and performed deeper dives in intensively fished areas. These results suggest SAFS forage in the same habitats targeted by commercial squid and finfish fisheries, where they compete for demersal resources by performing a high frequency of deep dives. The implications of our findings are discussed within the broader context of local prey-field dynamics and fisheries-management. This study represents one of the most comprehensive investigations of SAFS movement ecology and advances our understanding of seal-fishery interactions in the Falkland Islands EEZ – a topic of increasing management concern. Importantly, this work can support conservation efforts for this globally significant SAFS population and contribute to long-term marine management objectives of the Falkland Islands fishery.http://www.sciencedirect.com/science/article/pii/S2351989423002500Foraging behaviourSeal-fishery interactionSpatial overlapFisheriesSouth American fur seal |
| spellingShingle | Javed Riaz Rachael A. Orben Kayleigh A. Jones Megan Shapiro Andreas Winter Paul Brickle Alastair M.M. Baylis Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands Global Ecology and Conservation Foraging behaviour Seal-fishery interaction Spatial overlap Fisheries South American fur seal |
| title | Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands |
| title_full | Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands |
| title_fullStr | Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands |
| title_full_unstemmed | Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands |
| title_short | Spatial overlap between South American fur seal foraging effort and commercial trawl fisheries in the Falkland Islands |
| title_sort | spatial overlap between south american fur seal foraging effort and commercial trawl fisheries in the falkland islands |
| topic | Foraging behaviour Seal-fishery interaction Spatial overlap Fisheries South American fur seal |
| url | http://www.sciencedirect.com/science/article/pii/S2351989423002500 |
| work_keys_str_mv | AT javedriaz spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT rachaelaorben spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT kayleighajones spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT meganshapiro spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT andreaswinter spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT paulbrickle spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands AT alastairmmbaylis spatialoverlapbetweensouthamericanfursealforagingeffortandcommercialtrawlfisheriesinthefalklandislands |