Mangrove Nurseries: Factors affecting juvenile fish in mangrove forests

Found in the interface of land and sea, tropical mangrove forests are widely recognized as important nursing and feeding grounds for a variety of juvenile fish and invertebrates, often with completely different adult habitats. The complex root structures of mangrove trees, such as the prop roots of Rhizophora and the pencil like pneumatophores of Avicennia trees are believed to provide juvenile fish shelter and protection from predators while they develop. However the importance of a structurally complex mangrove might vary depending on the trophic level and life history of the fish species. Furthermore, a variety of other environmental factors such as the shallow depth of mangrove waters, tidal cycles and turbidity may combine with root structures to affect juvenile fish. With this study Bhanu from NCBS aims to investigate the effect of structural complexity on the abundance and composition of juvenile fish within mangrove forests in South Andamans. As part of this study she will also try to compare differences in mangrove forests inside the Mahatma Gandhi Marine National Park with mangrove patches outside, as well confirm the results of my data with experiments in the field.

ANURAN DOCUMENTATION AT ANET

The Andaman and Nicobar Islands are home to a unique assemblage of frogs, with a considerable proportion of endemics (about 50%). We have been documenting their status and occurrence in and around the ANET base in different habitat types. This region is rich in frog diversity with seven of the eight known species occurring, from ubiquitous generalists like the common toad (Duttaphrynus melanostiictus) to narrow, range-restricted endemics like the Andamans ‘painted’ frog (Fejervarya andamanensis) representing three different families. Disturbances in the evergreen forest habitat and scarcity of fresh-water bodies render them more vulnerable to environmental fluctuations than any other group of vertebrates.
List of frog species found in the ANET base
Common name Scientific name
Common Asian toad Duttaphrynus melanostictus
Narrow-mouthed frog Microhyla chakrapanii
Andaman bullfrog Kaloula baleata ghoshi
Mangrove frog Fejervarya cf. cancrivora
Cricket frog Fejervarya cf. limnocharis
Andamans ‘painted’ frog Fejervarya andamanensis
Skittering frog Limnonectes hacsheana
Andaman bullfrog Kaloula baleata ghoshi

MEASURING THE EFFECTIVENESS OF NO-TAKE RESERVES IN PROTECTING REEF FISH COMMUNITIES IN THE ANDAMAN ISLANDS - conducted by Sapna from NCBS

Coral reef fishing results in direct loss of diversity and abundance of fish populations on coral reefs. The fishery typically targets higher trophic groups that play important functional roles on reefs, making this system particularly vulnerable to the effects of over exploitation, with impacts that flow to the rest of the ecosystem, reducing its overall resilience and is implicated in reef collapse. Marine Protected Areas (MPAs) protect part of the reef from the negative impacts of fishing through the creation of no-take zones and through management of fishing practices. Moreover, protected fish populations inside the MPAs can help replenish fished populations outside through emigration of fish to fished areas. However, with reefs being subjected to ever increasing fishing pressures, there is further depletion of fish stocks which may have serious consequences for reef health and recovery. This study aims to assess whether MPAs in South Andamans are indeed effective in protecting fish populations within the reserve and generating spill-over of fish to nearby reefs, thereby reducing the impacts of fishing.
The study area for this project is the Mahatma Gandhi Marine National Park located in Wandoor, South Andaman Islands. The study will be conducted from December 2011 to May 2012. Coral reefs inside and outside the protected area will be sampled to assess fishing impacts and spillover effects. Data will be collected through SCUBA diving and social interviews. This study will help assess the effectiveness of MPAs and their importance in supporting local fisheries through mitigation of fishing impacts in unprotected reef areas.

Lacadives at ANET

Lacadives has always believed that Scuba Diving should extend beyond leisure and enjoyment, and used as a powerful way of spreading awareness and knowledge about marine ecosystems and life underwater. Over the past 15 years, in Lakshadweep and in Havelock, the instructors at Lacadives have taught people to see and breathe underwater using masks and scuba tanks, and therefore encourage them to open their eyes to the fine balance of the ocean’s ecosystems, the intricate relationships between its inhabitants and the various adaptations that allow them to exist. This longstanding aim has been able to find further focus as a result of the collaborative partnership with ANET since 2010. Lacadives’ primary goal in ANET is to facilitate researchers and students in their projects and education programs related to Marine Ecology, Coral Reef Monitoring and Fisheries science. ANET as a Centre for Island Ecology studies 6 main ecosystems, Coral Reefs being one that Lacadives facilitates the study of. This has made ANET’s tie-up with NCBS extremely valuable, furthering the education of Masters students and facilitating researchers from various institutions studying Coastal and Marine Ecology. We have also trained the Marine Police Force of the Andaman and Nicobar Islands and The Department of Environment and Forests in support of ANET’s extensive work with the local administration.
Lacadives is also actively involved in ANET’s education programs for school and college students,taking them diving / snorkeling to the reef followed by presentations, discussions and analyzing the reef, as witnessed in relation to the topics covered in their curriculum. Most of our school modules are combined with dive certification courses, the outcome of which is of great value to students - certifying them as open water divers while simultaneously covering a significant portion of their physics and biology syllabus as part of the dive theory. In our own diving everyday, we also record water temperatures, regeneration, indicator species and composition and reef health, hoping that such information will not only be of value to researchers and scientists but also help recreational divers expand their views on the ocean and marine resources and involve people in the protection and conservation of the immense diversity of the coral reefs in the Andaman and Nicobar Islands.

New Staff Accommodation

For some years now the ANET team has consisted of a small group of people that live on the property in the stilted cottages that so many of our guests have come to love. As the scale of our operations has increased and we have a much larger influx of guests ( in the form of students and researchers), we have felt the need to make more of these cottages available to guests, therefore requiring us to renovate and build new accommodation for the ANET staff. At the start of this season we embarked on various infrastructural increments and renovations and the new staff accommodation was one such accomplishment. A large and airy cottage block with three rooms and one attached bathroom hosts 8 of the ANET staff who are now in close proximity to the kitchen and common area but also have a space of their own with a veranda and a view of the trees.