The India MPA Workshop Proceedings. Social Dimensions of Marine Protected Areas Implementation in India: do Fishing Communities Benefit? 21-22 January 2009, IMAGE Auditorium, Chennai, India

In the current context of natural resource management, marine protected areas (MPAs) are being widely propagated as an important tool for the conservation of marine and fisheries resources. The International Collective in Support of Fishworkers (ICSF) recently undertook a series of studies on MPAs in India to highlight the various legal, institutional, policy and livelihoods issues that confront fishing and coastal communities. In order to discuss the findings of these case studies and to suggest proposals for livelihood-sensitive conservation and management of coastal and fisheries resources through participatory processes, ICSF organized a two-day workshop on ‘Social Dimensions of Marine Protected Area Implementation in India: Do Fishing Communities Benefit?’ at Chennai on 21-22 January 2009. This publication—the India MPA Workshop Proceedings—contains the prospectus of the workshop, a report of the proceedings and the consensus statement that was reached by organizations and individuals who particapated in the workshop. This publication will be useful for fishworkers, non-governmental organizations, policymakers, trade unions, researchers and others interested in natural resource management and coastal and fishing communities.

The control of indirect effects of biomanipulation

Results from long-term investigations on biomanipulation show that indirect effects are at least as important as direct effects are for the stability of biomanipulation. Three types of indirect effects can be distinguished: (1) a change in quantity or quality of the resource base, (2) behavioural change of the prey, and (3) development of anti-predator traits. Although indirect effects of type (2), (e.g. a change in the pattern of vertical migration of zooplankton), and type (3), (e.g. development of helmets and neck teeth in Daphnia), are important mechanisms, the most essential indirect effects regarding biomanipulation belong to type (1). An example of the latter will be demonstrated: the complex of indirect effects of enhanced grazing by large herbivores on the phosphorus metabolism of the lake. It is concluded that control of the indirect effects is absolutely necessary to stabilize biomanipulation measures, but this is much more difficult than the control of direct effects and needs deeper insights into the structuring mechanisms of food webs. Proper management of fish stocks, in combination with the control of phosphorus load and/or the physical conditions, seems to be the most promising way of controlling the indirect effects of biomanipulation.

Rélations hydrométéorologiques sur les côtes du Golfe de Guinée: influence de l'orientation de la côte

The Gulf of Guinea is remarkable for its abundant precipitations and negative anomalies of the surface water temperature. This originality comes from the southern monsoon which transfers the cold season to the middle of northern summer up to latitude 10 degrees North. Yearly precipitations, which can vary along the coast, are well in correlation with coast crossing air flow (r=0.71) and with the sea-air temperature difference (r=0.72). Precipitations provide a better correlation with surface temperatures (0.72) than with salinities (-0.63). The wind influence upon negative anomaly of the surface temperature is more clear on N-S coast (r=0.98) than on W-E coast (r=0.73) of the Gulf. Temporal correlations calculated on 16 years of observations in Pointe-Noire are in connection with previous spatial correlations. Coastal hydroclimates are thus likely to be deduced from meteorology.

Use of stereo camera systems for assessment of rockfish abundance in untrawlable areas and for recording pollock behavior during midwater trawls

We describe the application of two types of stereo camera systems in fisheries research, including the design, calibration, analysis techniques, and precision of the data obtained with these systems. The first is a stereo video system deployed by using a quick-responding winch with a live feed to provide species- and size- composition data adequate to produce acoustically based biomass estimates of rockfish. This system was tested on the eastern Bering Sea slope where rockfish were measured. Rockfish sizes were similar to those sampled with a bottom trawl and the relative error in multiple measurements of the same rockfish in multiple still-frame images was small. Measurement errors of up to 5.5% were found on a calibration target of known size. The second system consisted of a pair of still-image digital cameras mounted inside a midwater trawl. Processing of the stereo images allowed fish length, fish orientation in relation to the camera platform, and relative distance of the fish to the trawl netting to be determined. The video system was useful for surveying fish in Alaska, but it could also be used broadly in other situations where it is difficult to obtain species-composition or size-composition information. Likewise, the still-image system could be used for fisheries research to obtain data on size, position, and orientation of fish.

Simple broodstock management to control indirect selection and inbreeding: Indian carp example

Following a survey of the important traits of Indian carp broodstock at some southern Indian hatcheries, it was found that the broodstock selection was size selective, exerting strong, negative selection of prematuration growth rate and positive selection on age at first maturation. This meant that the hatchery bred inadvertently slower growing and later maturing individuals. Details are given of approaches to avoid such negative selection and minimize inbreeding.

Indirect validation of the age-reading method for Pacific cod (Gadus macrocephalus) using otoliths from marked and recaptured fish

Two examples of indirect validation are described for age-reading methods of Pacific cod (Gadus macrocephalus). Aging criteria that exclude faint translucent zones (checks) in counts of annuli and criteria that include faint zones were both tested. Otoliths from marked and recaptured fish were used to back-calculate the length of each fish at the time of its release by using measurements of the area of annuli. Estimated fish size at time of release and actual observed fish size were similar, supporting the assumption that translucent zones are laid down on an annual basis. A second method for validating reading criteria used otolith age and von Bertalanffy parameters, estimated from the tagging data, to predict how much each fish grew in length after tagging. We found that otolith aging criteria applied to otoliths from tagged and recovered Pacific cod predicted quite accurately the growth increments that we observed in these specimens. These results provide further evidence that the current aging criteria are not underestimating the age of the fish and support our current interpretation of checks (i.e., as subannual marks). We expect these indirect validations to advance age determination for Pacific cod, which in turn would enhance development of stock assessment methods based on age structure for this species in the eastern Bering Sea.

Indirect estimates of natural mortality rate for arrowtooth flounder (Atheresthes stomias) and darkblotched rockfish (Sebastes crameri)

Indirect estimates of instantaneous natural mortality rate (M) are widely used in stock assessment and fisheries management. They are essentially a form of meta-analysis, in which prior information on M and key life history parameters from a variety of stocks is used to estimate M for the stock in question.