Seagrass conservation and monitoring in Myanmar: the biodiversity, distribution and coverage of seagrasses in the Tanintharyi and Rakhine

Surveys on seagrass taxonomy, distribution and extent were carried out in 14 locations within Myeik Archipelago and along the Rakhine Coast.

Fishery resource assessment and monitoring in the development and control of fisheries in the Lake Volta

Gill-netting and rotenoning have been used for assessing and monitoring fish stock abundance in Volta Lake. The lake and the main gear types used on it have been described. Before a gill-net sampling plan was set up, a preliminary survey was undertaken which largely determined the final form of the plan. An investigation as to whether or not the lake was being overfished concluded that it was being underfished. Commercial and experimental catch data analyses disclosed that the adults of the small species were being little utilized. Commercial sized species were also not being harvested according to their apparent proportion in the population. Production is presently fluctuating between approximately 37,000 and 40,000 tonnes. A high correlation between commercial and experimental catch was realized. Developments which have followed in the wake of stock assessment and monitoring studies include: introduction of monofilament nylon net, development of a special scoop net to permit mass harvest of clupeids after they have been attracted to light, and the design of a larger canoe which would help to extend the fishery into open water. New regulation and management policies will have to be formulated in the light of new findings before a rational exploitation of all the species can be achieved.

Lessons from the breeding program of rohu

For the first time in India, selective breeding work has been initiated at the Central Institute of Freshwater Aquaculture, Bhubaneswar, India in collaboration with the Institute of Aquaculture Research (AKVAFORSK), Norway. Rohu has been chosen as the model species because it enjoys the highest consumer preference among Indian major carps (IMC) although its performance was observed to be slower than other IMC. As this was the first ever selection work on any Indian major carp, many procedures and techniques for successful implementation of the programs were standardized (i.e. production of full-sib groups, establishment of model hatchery for selective breeding of carps, rearing of full-sib groups in partitioned nursery ponds, individual tagging with the Passive Integrated Transponder (PIT) tag, communal rearing, sampling, data analysis, field testing and dissemination of improved rohu). After four generations of selection, an average of 17 per cent higher growth per generation was observed in improved rohu.

New challenges in lake and river monitoring

Freshwater ecosystems are highly dynamic and change on time-scales that range from a few hours to several months. The development of models that simulate these processes is often hampered by the lack of sufficient data to parameterize the processes and validate the models. In this article, I review some of the challenges posed by this lack of information and suggest ways in which they can be met by using automatic monitoring systems. One of these studies is the project tempQsim (EVK1-CT2002-00112) funded by the European Commission. In this project, detailed field and model analyses have been performed at eight catchment study sites in south and south-east Europe. A number of perceptual models for the study sites have been established, and results are being used to improve selected catchment models and provide a more adequate description of pollution dynamics. Results from the extensive field studies and model tests are now being used to derive recommendations for more tailored monitoring concepts in highly dynamic, but ‘data scarce’ environments, such as are frequently found in Mediterranean river basins. The author includes implications of the EU Water Framework Directive on monitoring methods.

The potential of community fish refuges (CFRs) in rice field agro-ecosystems for improving food and nutrition security in the Tonle Sap region

The fisheries sector in Cambodia contributes 8%–12% to national GDP and 25% - 30% to agricultural GDP, with an estimated 4.5 million people involved in fishing and associated trades. Fish and other aquatic animals are important food sources, contributing an estimated national average of 60% - 70% of total animal protein intake. Of the 2013 total fish production, 550,000 metric tons were harvested from freshwater habitats, of which rice field fisheries and small-scale family fisheries contributed approximately 20%. The productivity and value of rice field fisheries to households in rural Cambodia has been highlighted in a number of previous studies. The Fisheries Administration of the Ministry of Agriculture, Forestry and Fisheries plans to increase productivity from rice field fisheries and aquaculture at an annual rate of 15% to maintain supply for a growing population. This report draws mainly on the baseline and monitoring data from the Rice Field Fisheries Enhancement Project (RFFEP) during its implementation between 2012 and 2014. Reference is also made to the Fish on Farms project to highlight the relative contribution of fish from small-scale aquaculture compared to wild-caught fish.

Lakes - Classification & Monitoring: a strategy for the classification of lakes

This is the report on Lakes – Classification and Monitoring, a strategy for the classification of lakes by the National Rivers Authority. This report describes a scheme for the assessment and monitoring of water and ecological quality in standing waters, greater than about 1ha in area, in England and Wales although it is generally relevant to Northwest Europe. Thirteen hydrological, chemical and biological variables are used to characterize the standing water body in any current sampling. Statistical testing on the chemical variables showed that at least six samples during a year would be needed to produce a representative sampling mean; but in this scheme the choice of variables minimizes logistic cost by not using boat sampling and time costs by not demanding extensive taxonomic work. Standing waters are classified in a state-changed system in which the contemporary values of the variables are compared with a reference baseline state and then placed in categories of percentage change from this baseline. The scheme is presently designed for use at about five year intervals on all lakes greater than 2ha area plus additional lakes of significant amenity or conservation interest.

Staging ovaries of Haddock (Melanogrammus aeglefinus): implications for maturity indices and field sampling practices

We build on recent efforts to standardize maturation staging methods through the development of a field-proof macroscopic ovarian maturity index for Haddock (Melanogrammus aeglefinus) for studies on diel spawning periodicity. A comparison of field and histological observations helped us to improve the field index and methods, and provided useful insight into the reproductive biology of Haddock and other boreal determinate fecundity species. We found reasonable agreement between field and histological methods, except for the regressing and regenerating stages (however, differentiation of these 2 stages is the least important distinction for determination of maturity or reproductive dynamics). The staging of developing ovaries was problematic for both methods partly because of asynchronous oocyte hydration during the early stage of oocyte maturation. Although staging on the basis of histology in a laboratory is generally more accurate than macroscopic staging methods in the field, we found that field observations can uncover errors in laboratory staging that result from bias in sampling unrepresentative portions of ovaries. For 2 specimens, immature ovaries observed during histological examination were incorrectly assigned as regenerating during macroscopic staging. This type of error can lead to miscalculation of length at maturity and of spawning stock biomass, metrics that are used to characterize the state of a fish population. The revised field index includes 3 new macroscopic stages that represent final oocyte maturation in a batch of oocytes and were found to be reliable for staging spawning readiness in the field. The index was found to be suitable for studies of diel spawning periodicity and conforms to recent standardization guidelines.

Monitoring well-being and changing environmental conditions in coastal communities: development of an assessment method

The intersection of social and environmental forces is complex in coastal communities. The well-being of a coastal community is caught up in the health of its environment, the stability of its economy, the provision of services to its residents, and a multitude of other factors. With this in mind, the project investigators sought to develop an approach that would enable researchers to measure these social and environmental interactions. The concept of well-being proved extremely useful for this purpose. Using the Gulf of Mexico as a regional case study, the research team developed a set of composite indicators to be used for monitoring well-being at the county-level. The indicators selected for the study were: Social Connectedness, Economic Security, Basic Needs, Health, Access to Social Services, Education, Safety, Governance, and Environmental Condition. For each of the 37 sample counties included in the study region, investigators collected and consolidated existing, secondary data representing multiple aspects of objective well-being. To conduct a longitudinal assessment of changing wellbeing and environmental conditions, data were collected for the period of 2000 to 2010. The team focused on the Gulf of Mexico because the development of a baseline of well-being would allow NOAA and other agencies to better understand progress made toward recovery in communities affected by the Deepwater Horizon oil spill. However, the broader purpose of the project was to conceptualize and develop an approach that could be adapted to monitor how coastal communities are doing in relation to a variety of ecosystem disruptions and associated interventions across all coastal regions in the U.S. and its Territories. The method and models developed provide substantial insight into the structure and significance of relationships between community well-being and environmental conditions. Further, this project has laid the groundwork for future investigation, providing a clear path forward for integrated monitoring of our nation’s coasts. The research and monitoring capability described in this document will substantially help counties, local organizations, as well state and federal agencies that are striving to improve all facets of community well-being.

Development, validation, and utilization of a competitive enzyme-linked immunosorbent assay for the detection of antibodies against Brucella species in marine mammals

A competitive enzyme-linked immunosorbent assay (cELISA) was developed by using a whole-cell antigen from a marine Brucella sp. isolated from a harbor seal (Phoca vitulina). The assay was designed to screen sera from multiple marine mammal species for the presence of antibodies against marine-origin Brucella. Based on comparisons with culture-confirmed cases, specificity and sensitivity for cetacean samples tested were 73% and 100%, respectively. For pinniped samples, specificity and sensitivity values were 77% and 67%, respectively. Hawaiian monk seal (Monachus schauinslandi; n = 28) and bottlenose dolphin (Tursiops truncatus; n = 48) serum samples were tested, and the results were compared with several other assays designed to detect Brucella abortus antibodies. The comparison testing revealed the marine-origin cELISA to be more sensitive than the B. abortus tests by the detection of additional positive serum samples. The newly developed cELISA is an effective serologic method for detection of the presence of antibodies against marine-origin Brucella sp. in marine mammals.