scholarly journals Marine reserve benefits and recreational fishing yields: The winners and the losers

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0237685
Author(s):  
Mohsen Kayal ◽  
Marine Cigala ◽  
Eléonore Cambra ◽  
Nelly Soulat ◽  
Manon Mercader ◽  
...  

Marine reserves constitute effective tools for preserving fish stocks and associated human benefits. However, not all reserves perform equally, and predicting the response of marine communities to management actions in the long run is challenging. Our decadal-scale survey of recreational fishing yields at France’s 45-year old Cerbère-Banyuls marine reserve indicated significant protection benefits, with 40–50% higher fishing yields per unit effort in the partial-protection zone of the reserve (where fishing is permitted but at a lower level) than in surrounding non-reserve areas. Over the period 2005–2014, catch per unit effort (CPUE) declined both inside and outside the reserve, while weight per unit effort (WPUE) increased by 131% inside and decreased by 60% outside. Different CPUE and WPUE trajectories among fish families indicated changing catch assemblages, with yields increasing for the family most valued by fisheries, Sparidae (the ecological winners). However, reserve benefits were restricted to off-shore fishermen (the social winners), as on-shore yields were ~4 times lower and declining, even inside the reserve. Our study illustrates how surveys of recreational fishing yields can help evaluate the effectiveness of marine protected areas for key social and ecological protagonists. We show that, more than four decades after its establishment, fishing efficiencies at the historical Cerbère-Banyuls marine reserve are still changing, but benefits in terms of catch abundance, weight, and composition remain predominantly restricted to off-shore fishermen. Further regulations appear necessary to guarantee that conservation strategies equitably benefit societal groups.

2020 ◽  
Author(s):  
Mohsen Kayal ◽  
Marine Cigala ◽  
Eléonore Cambra ◽  
Nelly Soulat ◽  
Manon Mercader ◽  
...  

AbstractMarine reserves constitute effective tools for preserving fish stocks and associated human benefits. However, not all reserves perform equally, and predicting the response of marine communities to management actions in the long run is challenging. Our decadal-scale survey of recreational fishing yields at France’s 45-year old Cerbère-Banyuls marine reserve indicated significant protection benefits, with 40-50% higher fishing yields per unit effort in the partial-protection zone of the reserve (where fishing is permitted but at a lower level) than in surrounding non-reserve areas. Over the period 2005-2014, catch per unit effort (CPUE) showed a similar pattern of decline inside and outside the reserve while weight per unit effort (WPUE) increased by 131% inside and decreased by 60% outside. Different CPUE and WPUE trajectories among fish families indicated changing catch assemblages, with yields increasing for the family most valued by fisheries, Sparidae (the ecological winners). However, reserve benefits were restricted to off-shore fishermen (the social winners), as on-shore yields were ∼4 times lower and declining, even inside the reserve. Our study illustrates how surveys of recreational fishing yields can help evaluate the effectiveness of marine protected areas for key social and ecological protagonists. We show that, more than four decades after its establishment, fishing efficiencies at the historical Cerbère-Banyuls marine reserve are still changing, but benefits in terms of catch abundance, weight, and composition remain predominantly restricted to off-shore fishermen. Further regulations appear necessary to guarantee that conservation strategies equitably benefit societal groups.


2016 ◽  
Vol 74 (1) ◽  
pp. 263-276 ◽  
Author(s):  
Leigh M. Howarth ◽  
Pascal Dubois ◽  
Paul Gratton ◽  
Matthew Judge ◽  
Brian Christie ◽  
...  

This study investigated the effects of a community-led temperate marine reserve in Lamlash Bay, Firth of Clyde, Scotland, on commercially important populations of European lobster (Homarus gammarus), brown crab (Cancer pagurus), and velvet swimming crabs (Necora puber). Potting surveys conducted over 4 years revealed significantly higher catch per unit effort (cpue 109% greater), weight per unit effort (wpue 189% greater), and carapace length (10–15 mm greater) in lobsters within the reserve compared with control sites. However, likely due to low levels of recruitment and increased fishing effort outside the reserve, lobster catches decreased in all areas during the final 2 years. Nevertheless, catch rates remained higher within the reserve across all years, suggesting the reserve buffered these wider declines. Additionally, lobster cpue and wpue declined with increasing distance from the boundaries of the marine reserve, a trend which tag–recapture data suggested were due to spillover. Catches of berried lobster were also twice as high within the reserve than outside, and the mean potential reproductive output per female was 22.1% greater. It was originally thought that higher densities of lobster within the reserve might lead to greater levels of aggression and physical damage. However, damage levels were solely related to body size, as large lobsters >110 mm had sustained over 218% more damage than smaller individuals. Interestingly, catches of adult lobsters were inversely correlated with those of juvenile lobsters, brown crabs, and velvet crabs, which may be evidence of competitive displacement and/or predation. Our findings provide evidence that temperate marine reserves can deliver fisheries and conservation benefits, and highlight the importance of investigating multispecies interactions, as the recovery of some species can have knock-on effects on others.


2006 ◽  
Vol 63 (8) ◽  
pp. 1373-1385 ◽  
Author(s):  
Mark N. Maunder ◽  
John R. Sibert ◽  
Alain Fonteneau ◽  
John Hampton ◽  
Pierre Kleiber ◽  
...  

AbstractDespite being one of the most common pieces of information used in assessing the status of fish stocks, relative abundance indices based on catch per unit effort (cpue) data are notoriously problematic. Raw cpue is seldom proportional to abundance over a whole exploitation history and an entire geographic range, because numerous factors affect catch rates. One of the most commonly applied fisheries analyses is standardization of cpue data to remove the effect of factors that bias cpue as an index of abundance. Even if cpue is standardized appropriately, the resulting index of relative abundance, in isolation, provides limited information for management advice or about the effect of fishing. In addition, cpue data generally cannot provide information needed to assess and manage communities or ecosystems. We discuss some of the problems associated with the use of cpue data and some methods to assess and provide management advice about fish populations that can help overcome these problems, including integrated stock assessment models, management strategy evaluation, and adaptive management. We also discuss the inappropriateness of using cpue data to evaluate the status of communities. We use tuna stocks in the Pacific Ocean as examples.


2021 ◽  
Vol 46 (4) ◽  
Author(s):  
Camila PRIMITIVO ◽  
Alexandre SCHIAVETTI ◽  
Kátia Meirelles Felizola FREIRE

The aim of this study was to analyze the oceanic recreational fishing in the Royal Charlotte Bank, state of Bahia, Brazil. Only data from an oceanic recreational fishing operator based in the municipality of Canavieiras, southern Bahia, were used, from 2012 to 2017. Overall, 103 fish specimens were caught and released, during this period, belonging to the following species: Makaira nigricans, Kajikia albida, and Istiophorus platypterus. Fishery operations occurred from October to March, with the highest catch in number in December (56.3%). The largest annual catch was recorded in 2013, with 39 individuals. The catch per unit effort ranged from 1.0 to 1.4 fishes per trip, with the highest value in December. Even though data presented here are partial, they can help to establish a strategic scenario for the fishing sector in Bahia, along with data from other fishing sectors (artisanal, industrial, subsistence and scientific).


2014 ◽  
Vol 18 (2) ◽  
pp. 39-49
Author(s):  
Sabry El-Serafy ◽  
Alaa El-Haweet ◽  
Azza El-Ganiny ◽  
Alaa El-Far

Forecasting ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 39-55
Author(s):  
Rodgers Makwinja ◽  
Seyoum Mengistou ◽  
Emmanuel Kaunda ◽  
Tena Alemiew ◽  
Titus Bandulo Phiri ◽  
...  

Forecasting, using time series data, has become the most relevant and effective tool for fisheries stock assessment. Autoregressive integrated moving average (ARIMA) modeling has been commonly used to predict the general trend for fish landings with increased reliability and precision. In this paper, ARIMA models were applied to predict Lake Malombe annual fish landings and catch per unit effort (CPUE). The annual fish landings and CPUE trends were first observed and both were non-stationary. The first-order differencing was applied to transform the non-stationary data into stationary. Autocorrelation functions (AC), partial autocorrelation function (PAC), Akaike information criterion (AIC), Bayesian information criterion (BIC), square root of the mean square error (RMSE), the mean absolute error (MAE), percentage standard error of prediction (SEP), average relative variance (ARV), Gaussian maximum likelihood estimation (GMLE) algorithm, efficiency coefficient (E2), coefficient of determination (R2), and persistent index (PI) were estimated, which led to the identification and construction of ARIMA models, suitable in explaining the time series and forecasting. According to the measures of forecasting accuracy, the best forecasting models for fish landings and CPUE were ARIMA (0,1,1) and ARIMA (0,1,0). These models had the lowest values AIC, BIC, RMSE, MAE, SEP, ARV. The models further displayed the highest values of GMLE, PI, R2, and E2. The “auto. arima ()” command in R version 3.6.3 further displayed ARIMA (0,1,1) and ARIMA (0,1,0) as the best. The selected models satisfactorily forecasted the fish landings of 2725.243 metric tons and CPUE of 0.097 kg/h by 2024.


2021 ◽  
Author(s):  
Geneviève Nesslage ◽  
Vyacheslav Lyubchich ◽  
Paul Nitschke ◽  
Erik Williams ◽  
Churchill Grimes ◽  
...  

2021 ◽  
pp. 1-18
Author(s):  
PEMA KHANDU ◽  
GEORGE A. GALE ◽  
SARA BUMRUNGSRI

Summary White-bellied Heron Ardea insignis (WBH) is critically endangered, but we lack data on many aspects of its basic ecology and threats to the species are not clearly understood. The goal of this study was to analyse WBH foraging microhabitat selection, foraging behaviour, and prey preferences in two river basins (Punatsangchhu and Mangdechhu) in Bhutan which are likely home to one of the largest remaining populations of WBH. We also explored the relationship between the relative abundance of the WBH and prey biomass catch per unit effort within four foraging river microhabitats (pool, pond, riffle and run). Prey species were sampled in 13 different 100-m thalweg lengths of the rivers using cast nets and electrofishing gear. Riffles and pools were the most commonly used microhabitats; relative abundance was the highest in riffles. The relative abundance of WBH and prey biomass catch per unit effort (CPUE) also showed a weak but significant positive correlation (rs = 0.22). The highest biomass CPUE was observed in riffles while the lowest was found in the ponds. From the 97 prey items caught by the WBH, 95% of the prey were fish. The WBH mainly exploited three genera of fish (Garra, Salmo, and Schizothorax) of which Schizothorax (64%) was the most frequently consumed. This study provides evidence in support of further protection of critical riverine habitat and fish resources for this heron. Regular monitoring of sand and gravel mining, curbing illegal fishing, habitat restoration/mitigation, and developing sustainable alternatives for local people should be urgently implemented by the government and other relevant agencies. Further study is also required for understanding the seasonal variation and abundance of its prey species in their prime habitats along the Punatsangchhu and Mangdechhu basins.


Conservation ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 21-35
Author(s):  
Kazi Kamrul Islam ◽  
Mohammad Saifullah ◽  
Kimihiko Hyakumura

In the tropics, products and services provided by the traditional agroforestry systems (TAS) support the basic needs and promote the livelihood of millions of rural people. However, the outcomes and mitigation of TAS, in particular, the social and environmental issues are not systematically addressed. Thus, the objective of the study was to assess the economic, social and environmental outcomes of two important TAS in Bangladesh. This study reports results on prospective analyses using the Date palm and Jackfruit-based TAS practiced in the Jashore and Mymensingh districts of Bangladesh. The results revealed that the TAS enhanced farm productivity and the benefit–cost ratio of both systems were much higher than the general agricultural practices in Bangladesh. The TAS also improved resilience of rural farmers through more efficient water utilization, enhancing soil fertility, improving microclimate, controlling pests and diseases, and diversifying products. At the same time, the farmers’ problems were neglected due to the absence of farmers’ platforms, and also tradeoffs may arise; thus, the social aspects of the TAS farmers had not developed equally. Therefore, the study would recommend minimizing the tradeoffs through enhancing the conservation strategies at farmers’ levels to make the TAS more viable and sustainable land-use practices.


2016 ◽  
Vol 55 (2) ◽  
pp. 126-133
Author(s):  
Elliot H. Alhassan ◽  
Patrick K. Ofori-Danson ◽  
Francis K. E. Nunoo

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