Marine Biodiversity
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ISSN 2319-4361 (Indexed in Google Scholar) Volume 6 | Issue 1 January - March 2017 Special Issue Part 2 Marine Biodiversity Mangroves Fishes, Crabs Otters, Dolphins, Whales Conservation Policy SMOOTH-COATED OTTER Status Survey of Otter Species in Mangrove Habitat of Sindhudurga District, Maharashtra Satish Pande, Anant Gokhale, Ram Mone, Rajkumar Pawar, Rahul Lonkar, Prashant Deshpande, Dr. Satish Karmalkar and Sudhanwa Rajurkar (Ela Foundation, Pune; [Email: [email protected]]. Citation: Pande Satish, Anant Gokhale, Ram Mone, Introduction Rajkumar Pawar, Rahul Lonkar, Prashant Deshpande, Otters [Mustelidae Family] are poorly studied aquatic Dr. Satish Karmalkar and Sudhanwa Rajurkar. (2017). mammals. No comprehensive data for the populations Status Survey Of Otter Species In Mangrove Habitat Of and current status of this taxon is available for the Sindhudurga District, Maharashtra. Sindhudurga district, Maharashtra, India. The sporadic Ela Journal of Forestry and Wildlife 6(1): 329-346 sightings are rare, mostly in and around mangroves and the habitats are not easily accessible. In this scenario, the Date of Publication: present study provides scientifi c data for the conservation 31-3-2017 of this species. There are possibly six species of otter occurring in Asia out of which the Eurasian Otter (Lutra ISSN 2319-4361 lutra), Smooth-coated Otter (Lutrogale perspicillata), Copyright: © Pande Satish, Anant Gokhale, Ram Mone and Asian Small-clawed Otter (Aonyx cinerea), are 1,2,3 et. al. 2017 reported from India . Otter surveys are problematic due to diffi culty in Referee: R. Yosef direct detection of individuals in natural habitats and associated high costs of surveying rough and many times diffi cult to reach terrain. Hence, indirect methods of Dr Satish Pande, Ela Foundation, Pune Dr © Smooth-coated Otter in Sindhudurga district, Maharashtra Ela Journal of Forestry and Wildlife | www.elafoundation.org | mahaforest.nic.in | Vol. 6 Issue 1 / January - March 2017 | 329 SMOOTH-COATED OTTER recording tracks, foot marks, faeces or scent markings creeks. have become standard protocol. The ‘Standard Otter e) Species identifi cation: This was done from photographs Survey’ method4,5, focuses on the detection of otter and / or pugmarks and comparing them with diagnostic spraint (faeces) but may also include tracks (footprints) keys4 from published data. or holts (breeding dens) along river banks. In view of f) Survey Techniques4,5 Study was done strictly as per absence of data on otters from Sindhudurga district, the provisions of the WPA 1972. For the crepuscular Maharashtra, we undertook the fi rst systematic survey species like otters a combination of techniques were using the method described by Lenton4 and Bodkin5 and used. Estimate of otter presence was done by pooling supplementing them with camera traps, under-bridge data from all the six sampling techniques listed below: surveys and local information, to determine the status of 1. Visual Creek / River Boat Transects by non-intersecting otters in this region. The preliminary fi ndings from our line transects from boats by sailing along the tidal creeks, survey are presented in this paper. backwaters and rivers for each of the 12 creeks. 2. Bank Line Transects – (ISU). Shore based surveys Methodology using intensive search units (ISU) along the line transacts a) Objectives: have produced unbiased results5. We used ISU’s of 600 1. Document the diversity of otter species in the study m at 12 creeks. GPS locations of otter spraints / scats area. and sightings were recorded for all positive and negative 2. Record the distribution of otters in the study area. sites. 3. Document the habitat preference of otters. 3. Under Bridge Surveys are important because spraints b) Study Area (Transects): / scats tend to stay longer in these areas as compared to The survey for otters was conducted in Mangrove on open banks. GPS locations of otter spraints / scat and patches in the coastal areas in Sindhudurga district, sightings were recorded. Maharashtra. The northern most GPS coordinates of the 4. Modifi ed Scent Station Surveys: The prawn and crab study area (Vijaydurga-Vaghotan) were 16.510112 N and farms in the study areas were used as modifi ed scent 73.404418 E while the southernmost GPS coordinates stations. Such sites were visited to fi nd the presence or (Aronda-Terekhol) were 15.73682 N and 73.75741 E. The absence of otters. GPS locations of survey sights were creeks and backwaters in Sindhudurga where the survey recorded. transects were conducted included: 5. Trap Camera Surveys were conducted at randomly Vijaydurga Creek – Shanti River selected sites for theonfi rmation of presence of otters Vadatar Creek –Piyali River and identifi cation of otter species. Devgad Creek and backwaters 6. Supplementary data from questionnaire: The response Mithbav Creek – Naringre River from local fi shermen about the presence / absence of Achra Creek – Achra River otters was recorded during the creek-wise surveys. Kalaval - Tondavali Creek – Gad River Kolamb Creek and backwaters UNITS OF THE DATA: Karli Creek – Pithdhaval River 1. Otter Presence / Absence for study sites. Mochemadi Creek – Talavade River 2. Identifi cation of otter species. Aravali Creek and backwaters Aronda Creek and backwaters Observations and Results Terekhol Creek – Otawane River c) Number of visits and data analysis: Total 30 visits 1. Diversity of Otters in the Study Area were carried out during the period from November 2015 a. Species: Our survey revealed that only one species to June 2016 for the study of otters in the Sindhudurga of otter; the Smooth-coated Otter Lutrogale perspicillata district. Data was analyzed from February 2016 to was present in the mangrove habitats in all the twelve November 2016. creeks of Sindhudurga district. d) Consistency of Sampling: To assure consistency of b. Local names: Otters are generally well known sampling, same methods were used for transects, GPS among the fi shing community and are called as Hud, Ood methodology was used to record otter presence sites and Uda in Marathi language. and the same researchers conducted the survey in all 330 | Ela Journal of Forestry and Wildlife | www.elafoundation.org | mahaforest.nic.in | Vol. 6 Issue 1 / January - March 2017 SMOOTH-COATED OTTER 2. Otter Distribution and GPS Mapping: B] Otters were not recorded where: Presence of otter spraints and otter sightings were 1. human disturbance was signifi cant, important indicators of otter presence for recording their ii. coastal areas with infrastructure development, distribution. GPS coordinates of all survey sites including ii. sand dredging activity was ongoing, intensive survey units (ISU’s) were recorded. Smooth- iv. thick mangrove cover made accessibility to the water coated Otter Lutrogale perspicillata was present in all body impossible making this a false negative site, the 12 creeks. 5. Other observations: 3. Otter Presence Sites a) Distance from the sea: The farthest inland otter a. Creeks: The sites of otter presence are detailed as presence from the sea coast was 42.4 km for the GPS coordinates of each ISU (Table 1 to 12). The Kalaval-Tondavali creek. GPS Maps are also shown in Maps 1 to 12. Otter b ) Tidal effect: Near kharland bunds otters were best spraints are the most reliable indicators for the seen at low tides. It was recorded that the otters swim presence of otters. Otter spraints are visible on open away and towards the coast with high and low tide. banks along the creeks, on Kharland Scheme bunds However, the effect of tides on otter sighting was not and also on the coasts. However, they are not seen conclusively established for creeks. when the coasts are occupied by dense mangroves. Table 13 summarizes the otter presence / absence Discussion and Conclusions data for all the creeks. Smooth-coated Otter Lutrogale perspicillata is b. Under Bridge Surveys: In all 17 bridges in all the Vulnerable and is included in Appendix II of CITES 8,9. creeks in Sindhudurga district were surveyed for Otter surveys are diffi cult due to poor sightings and their otter presence. 16 bridges showed presence of otters occurrence in coastal habitats where surveys are not only as evident by spraints. We therefore conclude that time consuming and demand logistic supports6,7. Our otter spraints are reliably seen under bridges where survey using a combination of techniques revealed that they remain for a long time and old spraints could only one species, the Smooth-coated Otter Lutrogale also be seen and recognized by their brittleness and perspicillata was present in the mangrove habitats in all white colour. (Table 14). the twelve creeks of Sindhudurga district studied during c. Modifi ed Scent Station Surveys: 6 modifi ed scent our survey. The otter presence sites were mapped with stations were surveyed. These were crab and prawn GPS coordinates for all creeks. Otters mostly exhibit farms. Large sized spraints of otters (up to 3 m x 3 crepuscular habits, however we also rarely recorded m) were seen in all 6 stations. Otters were sighted them fi shing and swimming during the noon. Otters use in one station (n =4; Meethbav-Naringre creek). mangroves for cover and resting. Otter photographs could Hence, we conclude that Modifi ed Scent Stations be obtained using conventional cameras and trap cameras are reliable sites for presence of otters due to the with motion sensing and IR technology. The analysis of availability of abundance of food in a small area. our observation for predicting the best method for otter (Table 15). survey in our region, estimation of population and group f. Trap Camera Images: We could get otter pictures compositions, territory size, food preferences and threats in trap cameras installed in various sites that were is ongoing. previously documented positive for otter presence. 4. Habitat Preference: Recommendations: A] Otters were recorded in: We recommend that in view of absence of data on i. all creeks and backwaters with mangrove habitats, otters from other coastal districts of Maharashtra, otter ii.