Conservation Benefits of Temperate Marine Protected Areas: Variation among Fish Species

Abstract:  Marine protected areas, and other fishery management systems that impart partial or total protection from fishing, are increasingly advocated as an essential management tool to ensure the sustainable use of marine resources. Beneficial effects for fish species are well documented for tropical and reef systems, but the effects of marine protected areas remain largely untested in temperate waters. We compared trends in sport-fishing catches of nine fish species in an area influenced by a large (500-km²) towed-fishing-gear restriction zone and in adjacent areas under conventional fishery management controls. Over the period 1973–2002 the mean reported weight of above-average-sized (trophy) fish of species with early age at maturity and limited home range was greatest within the area influenced by the fishing-gear restriction zone. The reported weight of trophy fish of species that mature early also declined less and more slowly over time within the area influenced by the fishing-gear restriction zone. Importantly, the mean reported weight of trophy fish of species that mature late and those that undertake extensive spatial movements declined at the same rate in all areas. Hence these species are likely to require protected areas >500 km² for effective protection. Our results also indicated that fish species with a localized distribution or high site fidelity may require additional protection from sport fishing to prevent declines in the number or size of fish within the local population.     

Relative impacts at sites of dredged-material relocation in the coastal environment: a phylum-level meta-analysis approach

Phylum-level meta-analysis was applied to 192 samples from a variety of dredgings disposal and relocation sites around the coast of England and Wales. No consistent relationship was found between the disturbance status of macrobenthic communities within disposal sites and the nature or amount of dredgings disposed. Differences between samples within and outside disposal sites were generally smaller than differences between different sites and various patterns of impact were detected. It is concluded that dredgings disposal has two contrasting impacts on benthic communities. One, associated with organic enrichment, leads to communities dominated by annelids and nematodes. The other, associated with intense physical disturbance, favours large motile or armoured forms, such as bivalve molluscs and crustaceans. These effects may act antagonistically, and in a phylum-level meta-analysis may cancel each other out. None of the samples examined from offshore disposal sites was grossly disturbed, in terms of the proportional contribution to production from different phyla, and overall most samples ranged from moderately disturbed to undisturbed. The ecological impacts associated with the intertidal placement of material (beneficial use schemes) were comparable to those observed for the conventional sea disposal sites.     

Emergence pattern of loggerhead turtle (<Emphasis Type="Italic">Caretta caretta</Emphasis>) hatchlings from Kyparissia Bay,Greece

The present study describes the emergence pattern of loggerhead sea turtle hatchlings (Caretta caretta) from a nesting beach in Kyparissia Bay (Greece). We try to establish the role played by hatchling biometry, nest relocation and distance from nest to the sea on this emergence pattern. We surveyed a total of 32 nests, and found long emergence periods (mean = 6.7 nights). The majority of emergences occurred at night, mainly between 0030 and 0100 hours, and in small groups. Most of the hatchlings emerged from the nests the first night. We found no clear trend when we studied the effect of hatchling biometry between successive emergence days. We also found that relocation of the nests did not significantly affect the emergence pattern. However, we noted that in the relocated nests, hatchlings emerged in smaller groups. Emergence periods were inversely related to distance from the sea. In short, factors such as climate conditions, relocation and nest distance to the sea appear to have some effect on the emergence pattern. Therefore, they should be taken into account in both biological studies and management plans for sea turtle nesting beaches. Our results suggest leaving an extended period between the first emergence of hatchlings and the excavation of nests by researchers in future studies in the area.     

The Monitoring of UK Sewage Sludge Disposal Sites

In recent years there has been an increase in the intensity and frequency of environmental monitoring surveys at UK sewage sludge disposal sites. These have been carried out by the regulatory authorities and by the licensees. in order to ensure maximum efficiency, a coordinated and harmonised programme of monitoring has been developed. the programme concentrates on sediment chemical and biological quality but also includes assessments of water and fish quality

In England and Wales the Ministry of Agriculture, Fisheries and Food is the regulatory authority and the Water Authorities are the licensees. the Ministry's first priority is the collection of samples for temporal trend analysis but in addition, infrequent surveys are made to check the status of the disposal site and surrounding areas. in the periods between status surveys, regular spatial surveys designed to define the area of impact are carried out by the Water Authorities.     

Rapidly assessing cobenefits to advance threat-management alliances

Conservation strategies aimed at reducing threats to biodiversity can have significant implications for multiple sectors in a socioeconomic system, but these cobenefits are often poorly understood. For example, many of the threats to native species also impede agricultural production, yet agriculture is typically perceived as in competition with conservation objectives. Although a comprehensive, multiobjective decision analysis is usually beyond the scope and capacity of conservation decision makers, failing to incorporate key socioeconomic costs and benefits into conservation decision-making processes can result in missed opportunities for diversifying outcomes and creating cost-sharing multisectoral partnerships. We devised a straightforward and readily interpretable approach to incorporate cobenefits into a threat-management prioritization approach. We used it to analyze the agricultural cobenefits of implementing 9 invasive animal management strategies designed to ensure the persistence of 148 threatened species across Australia's Lake Eyre Basin over 50 years. A structured elicitation process with 24 participants (scientists, land managers, agriculturalists, and other stakeholders) was used to collect information on each strategy, including costs, technical and social feasibility, benefits to native threatened species, and cobenefits to agricultural production systems. The costs of targeted invasive animal management to save threatened species across the basin (AU$33 million/year) outweighed the overall benefits to the agricultural industry (estimated AU$226 million/year). The return on investment for these management strategies varied substantially when agricultural cobenefits were considered alongside threatened species benefits and showed synergies and challenges. Our approach demonstrates the value of incorporating cobenefits of conservation actions into cost-effectiveness analyses to guide potential investment and partnerships and to diversify implementation pathways.     

The outcomes of downward managerial mobility

Research examining the effects of unemployment among white collar workers has produced patterns of findings different to those for lower socio-economic groups. The present longitudinal questionnaire study examines the psychological impact of managerial job moves which are downward in status, and considers the effects of periods of unemployment between job changes. The results indicate that among managers the negative impact of downward status moves on psychological adjustment is greater than that of temporary role loss. These effects are associated with decrements in preceived growth and development opportunities at work. The relationship between work and non-work life for our understanding of psychological adjustment is considered.     

Suitability of selected North American grasshopper species as hosts for grasshopper parasites from Pakistan

Three species of Sacrophagidae (Diptera) and four of Scelionidae (Hymenoptera) that are parasites of grasshoppers or grasshopper eggs in Pakistan were imported into the United States and exposed to 16 and 24 species of North American grasshoppers representing the three major sub-families. The hosts that were provided were unacceptable, and the exotic parasites were not promising for control of American grasshoppers.     

Ammonium, but not nitrate, stimulates an increase in glutamine concentration in the haemolymph of Tridacna gigas

The concentration of glutamine in Tridacna gigas haemolymph increased >35-fold following exposure to sea water supplemented with ammonium (20 μM), but no increase was observed with nitrate (20 μM). Lack of a diel cycle, no decrease in haemolymph glucose levels, the expression patterns of glutamine synthetase in zooxanthellae and host, and the lack of glutamine release in response to nitrate supplementation all support the proposition that the increase in haemolymph glutamine is a product of the host and not the zooxanthellae. Unlike ammonium, nitrate accumulates rapidly in the haemolymph. It has no effect on the concentration of glutamine in the haemolymph, but there is an increase in arginine, histidine and lysine in the haemolymph, suggesting the release of these essential amino acids from zooxanthellae. Glutamine synthetase (GS) activity decreased markedly in the gill and less so in the mantle over a period of 6 d exposure to elevated ammonium (20 μM). In contrast, GS activity in zooxan- thellae doubled. The response of zooxanthellae in situ was confirmed by incubating freshly isolated zooxanthellae for 4 d in ammonium, which resulted in a ten-fold increase in GS activity. Comparison of the in situ response of zooxanthellae with that obtained in vitro indicates that the symbionts are likely to be exposed to ammonium concentrations lower than that found in the haemolymph. Received: 14 November 1997 / Accepted: 28 April 1998     

Estimating the Value of Non‐Use Benefits from Small Changes in the Provision of Ecosystem Services

Abstract: The unit of trade in ecosystem services is usually the use of a proportion of the parcels of land associated with a given service. Valuing small changes in the provision of an ecosystem service presents obstacles, particularly when the service provides non‐use benefits, as is the case with conservation of most plants and animals. Quantifying non‐use values requires stated‐preference valuations. Stated‐preference valuations can provide estimates of the public's willingness to pay for a broad conservation goal. Nevertheless, stated‐preference valuations can be expensive and do not produce consistent measures for varying levels of provision of a service. Additionally, the unit of trade, land use, is not always linearly related to the level of ecosystem services the land might provide. To overcome these obstacles, we developed a method to estimate the value of a marginal change in the provision of a non‐use ecosystem service—in this case conservation of plants or animals associated with a given land‐cover type. Our method serves as a tool for calculating transferable valuations of small changes in the provision of ecosystem services relative to the existing provision. Valuation is achieved through stated‐preference investigations, calculation of a unit value for a parcel of land, and the weighting of this parcel by its ability to provide the desired ecosystem service and its effect on the ability of the surrounding land parcels to provide the desired service. We used the water vole (Arvicola terrestris) as a case study to illustrate the method. The average present value of a meter of water vole habitat was estimated at UK£12, but the marginal value of a meter (based on our methods) could range between £0 and £40 or more.