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Availability: Creative Commons License This dataset is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Notes: Only data aggregated per 1-degree cell are available through OBIS. For access to additional data, the provider needs to be contacted.

Resource competition between fisheries and marine mammal continue to raise concern worldwide. Understanding this complex conflict requires data on spatial and dietary overlap of marine mammal and fisheries. In Uruguay, the South American sea lions population has been dramatically declining over the past decade. The reasons for this population decline are unknown but may include the following:
(1) direct harvesting;
(2) reduced prey availability and distribution as a consequence of environmental change; or
(3) biological interaction with fisheries. This study aims to determine resource overlap and competition between South American sea lions (SASL, Otaria flavescens, n=10) and the artisanal fisheries (AF), and the coastal bottom trawl fisheries (CBTF). more

We integrated data on sea lions diet (scat analysis), spatial and annual consumption estimates; and foraging behavior-satellite-tracking data from lactating SASL with data on fishing effort areas and fisheries landings. We found that lactating SASL are benthic divers and forage in shallow water within the continental shelf. SASL's foraging areas overlapped with CBTF and AF fisheries operational areas. Dietary analysis indicated a high degree of overlap between the diet of SASL and the AF and CBTF fisheries catch. The results of our work show differing degrees of spatial resource overlap with AF and CBTF, highlighting that there are differences in potential impact from each fishery; and that different management/conservation approaches may need to be taken to solve the fisheries-SASL conflict. Purpose: In this study we hypothesized that the biological interaction between SASL and fisheries may create sub-optimal foraging conditions for lactating females breeding in Isla de Lobos the second largest breeding colony.

The objectives of the present study were as follows:
(i) to examine the diving behavior of lactating SAS,
(ii) to determine the spatial distribution of foraging effort of lactating SASL,
(iii) to study the diet of lactating SASL, and
(iv) to integrate these data with information of spatial distribution of fishing catch and effort to quantify the trophic and spatial overlap between SASL and the Uruguayan artisanal and coastal bottom trawl fisheries.

Supplemental information: This research was funded by the US Marine Mammal Commission under the Grant no. E4047335 and the Office of Naval Research Grant N00014-08-1-1195, the E&P Sound and Marine Life Joint Industry Project of the International Association of Oil and Gas Producers. We would like to thanks Nelson Veiga, José Luis Veiga, Gabriel Pereyra, Leonardo Olivera, D.J. Shuman, H. Katz, R. Frau, S. Tavoni, M. García, M. Rivas for their invaluable assistance and collaboration during the field work. We are also thankful to C. Leiza (Parque Zoológico Lecoq, Uruguay) for providing tranquilizing darts dart, and the Marine Mammal Center (Sausalito, California, USA) for lending the capture nets. We would like to acknowledge the logistical support of DINARA. The present work was conducted under the permit #572/208 approved by DINARA (National Administration of Aquatic Resources), Ministry of Livestock, Agriculture and Fisheries, Uruguay. This dataset is a summarized representation of the telemetry locations aggregated per species per 1-degree cell.

Biology > Mammals
Marine, ASW, Uruguay, Otaria flavescens Shaw, 1800

Geographical coverage
ASW, Uruguay [Marine Regions]

Temporal coverage
16 January 2009 - 3 March 2009

Taxonomic coverage
Otaria flavescens Shaw, 1800 [WoRMS]

Occurrence of biota

University of the Republic of Uruguay (UDELAR), moredata creator

Related datasets
Published in:
OBIS-SEAMAP: Spatial Ecological Analysis of Megavertebrate Populations, more

Based on this dataset
Riet-Sapriza, F.G. et al. (2013). Foraging behavior of lactating South American sea lions (Otaria flavescens) and spatial–temporal resource overlap with the Uruguayan fisheries. Deep-Sea Res., Part II, Top. Stud. Oceanogr. 88-89: 106–119., more

Dataset status: Completed
Data type: Data
Data origin: Research: field survey
Metadatarecord created: 2015-03-23
Information last updated: 2015-03-23
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