Modelling spillover effects of a marine protected area in the Western Indian Ocean

Riad M A Sultan

doi:10.4314/wiojms.v20i2.4

Abstract

This study estimated the abundance gradient of fishes in the waters surrounding a marine protected area (MPA) and used this information as evidence of spillover from the MPA. Fish landing data were collected from trap fishermen over a 12-month period from the Blue Bay Marine Park on the west coast of Mauritius in the Western Indian Ocean. Two indicators of abundance were used: catch per trap, and number of fish per trap. A Generalised Linear Model was used to standardise the catch data by removing the effects of individual fishermen’s productivity from the abundance measurements while the negative-binomial distribution was used for the number of fish. The study found a slight declining gradient of catch beyond the MPA up to a distance of 4 km. The study also established that the individuals belonging to key species caught near the MPA were larger thanthose of the same species caught more than 4 km away. The negative gradient reinforces the evidence of spillover occurring from the MPA.

Highlights

In the context of this paper a marine protected area (MPA), or marine reserve, is a portion of ocean where fishing and other human activities are prohibited (Hannesson, 1998; Crowder et al, 2000; Sladek-Nowlis and Roberts, 1999; Lorenzo et al, 2016)
This paper investigates the evidence of spillover effects of a small MPA, the Blue Bay Marine Park (BBMP), located in a heavily fished area in the southeast of Mauritius
The results of this study show that catches were slightly higher in waters adjacent to of the Marine Park and the size of the fish near the reserve was relatively larger

Summary

Introduction

In the context of this paper a marine protected area (MPA), or marine reserve, is a portion of ocean where fishing and other human activities are prohibited (Hannesson, 1998; Crowder et al, 2000; Sladek-Nowlis and Roberts, 1999; Lorenzo et al, 2016). Evidence that MPAs can lead to spillover effects provides opportunities for them to be used as fisheries management tools to sustain fishers in the adjacent areas. This paper investigates the evidence of spillover effects of a small MPA, the Blue Bay Marine Park (BBMP), located in a heavily fished area in the southeast of Mauritius. Two marine parks and six fishing reserves have been established, while the process of establishing new protected areas and expanding existing ones is ongoing, especially as part of the marine spatial planning process (Smith, 2017)

Methods

Results

Discussion

Conclusion