Project

Which nursery is best for Peru’s baby smooth hammerhead sharks?

Species
  • Sharks
Years funded
  • 2021
Status
  • Active
Project types
  • Conservation
  • Research
Affiliation
  • Universidad Austral de Chile
Description

Eduardo’s project is looking to run stable isotope analyses to understand what baby hammerhead sharks are eating, and how they are using different habitats. He is focusing on three nursery areas that were identified in Peru, testing whether there are differences between the hammerhead populations in each nursery, and which baby hammerheads are in the best condition. This information will be used to inform conservation and management plans with focus on each nursery area or baby hammerhead population.

Which nursery is best for Peru’s baby smooth hammerhead sharks?

Eduardo Segura

Project leader
About the project leader

I have been interested in the interaction and connection between humans and marine ecosystems since I was a child. I was amazed by fishers’ stories about the big sharks or the sea lions they saw. Contact with fishers also helped me to understand the essential role of the ocean in coastal communities’ efforts to earn a livelihood. When I graduated as a marine biologist, I started working with rays and was very surprised that so little is known about their ecology, given that rays are such an important component of the Peruvian fishery. So I started working as a researcher...

PROJECT LOCATION : Peru
Project details

Which nursery area contributes the most benefits to the Smooth Hammerhead populations in Peruvian waters?

Key objective

The project aims to assess trophic niche (where and what they eat) and nutritional state (how fit they are) of juvenile Smooth Hammerhead in three shark nursery areas offshore northern Peru in order to inform where conservation efforts should be directed to benefit rapidly declining Smooth Hammerhead populations.

The study will be conducted in the northern Humboldt Current Ecosystem (NHCE) offshore Perú in the southeast Pacific Ocean (3.5° S to 10° S), a zone of high abundance of the Smooth Hammerhead sharks from the coastline to approximately 150 km offshore. The NHCE is part of the world´s four Major Eastern Boundary Upwelling Ecosystems (EBUEs), characterized by coastal upwelling and high fish productivity (Chavez & Messié, 2009). Three potential smooth hammerhead nursery areas were described in this zone based on frequent catches of neonates and juveniles of which one is located in the Tropical East Pacific Marine Province (TEP-MP), offshore Máncora harbour (Piura region). The other two in the Warm Temperate Southeastern Pacific Marine Province (WTSP-MP), offshore San José harbor (Lambayeque region), and offshore Salaverry port (La Libertad region).

Why is this important

Globally, abundance of Smooth Hammerhead shark has drastically declined over the past decade due to fishing. Three Smooth Hammerhead shark nursery areas were described offshore northern Peru. However, relative importance of each of them for Smooth Hammerhead recruitment is unknown up to date. As conservation of all areas is impossible, this study aims to evaluate the importance of each of the nursery areas for recruitment of juvenile Smooth Hammerhead to provide knowledge for conservation prioritization.

Background

The study will be conducted in the Humboldt Current System offshore Peru in the southeast Pacific Ocean, a zone of high abundance of the Smooth Hammerhead sharks from the coastline to approximately 150 km offshore. This zone is characterized by coastal upwelling and high fish productivity and accommodates important artisanal fishery. The smooth hammerhead populations are considered fully exploited fishery in Peru, but historically neonates and juveniles dominated fishery landings in summer. This fact led to a decree of closure of the smooth hammerhead fishery between January and March. Despite this closure, the smooth hammerhead catch quota has been decreasing and no biomass recovery has been observed. Shark nursery areas are costal zones of abundant food resources that accommodate juvenile sharks facilitating their growth and recruitment to adult populations. Three potential Smooth Hammerhead nursery areas were described in this zone based on frequent catches of neonates and juveniles of which one is located in the Tropical East Pacific Marine Province and the other two in the Warm Temperate Southeastern Pacific Marine Province. The IUCN recommended “the protection of known adult aggregation sites and nursery areas” of this species due to its essential ecological role as a top predator. Nevertheless, scientific evidence to assess the quality and contribution of these nursery areas to overall population recruitment are missing. Studies to obtain such evidence are essential to design appropriate Marine Protected Areas (MPAs) for effective conservation. In Peru, only three MPAs exist up to date, but none focuses on conservation of recruitment areas of open water marine species. One more MPA that included open water habitats has been proposed in the North of Peru, including smooth hammerhead nursery area, but its creation was not completed due to lack of scientific evidence of benefits for target species.

Aims & objectives

The aims and objectives of this project are:

  • To assess the diet and habitat use of juvenile smooth hammerhead in three nursery areas through analyses of stables isotopes of carbon, nitrogen and sulphur and fatty acids in muscle and liver tissues (slow and fast turnover rate) in order to identify their fishery stock structure and feeding grounds.
  • To determine and compare the nutritional status of the smooth hammerhead juveniles among the three nursery areas (protein and lipid content, and fatty acid composition) in muscle and liver in order to identify which nursery area provides superior conditions for juvenile survival and growth.
  • To elaborate a map that delineates areas in relation to the nutritional status of juvenile smooth hammerhead populations and propose the most important nursery areas that should be prioritized as a marine protected area in order to conserve populations of this species in Peruvian waters.