Ist Interim Report - mangroves.maharashtra.gov.in

Ela Foundation & Mangrove Cell

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Ist Interim Report

PROPOSAL FOR THE SURVEY OF

OTTER AND CROCODILE SPECIES IN MANGROVE HABITATS OF RATNAGIRI

DISTRICT, MAHARASHTRA

Principal Investigator:

Ela Foundation, Pune.

Co-Investigator:

Chief Conservator of Forests Mangroves, Mumbai

Principle Researcher from Ela Foundation:

Dr. Satish Pande, MB, MD, DNB, PhD (Ornithology); F.M.A.Sci., FLS

With

Ram Mone, Anant Gokhale, Rajkumar Pawar, Sudhanwa Rajurkar

April 2019 to September 2019


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Contents

Background … 3

Study Area … 3

Objectives … 3

Methodology for Otter and Crocodile Survey … 4

Observations … 7

Survey Maps with GPS locations … 11

Conclusions … 14

Survey Photographs … 15 to 17


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Background:

There are possibly six species of otter occurring in Asia –

1. Eurasian Otter (Lutra lutra),

2. Smooth-coated Otter (Lutrogale perspicillata),

3. Asian Small-clawed Otter (Aonyx cinerea),

4. Hairy-nosed Otter (Lutra sumatrana),

5. Japanese Otter (Lutra nippon) and

6. Sea Otter (Enhydra lutris).

Out of these, the first three species are reported from India.

(http://www.otterspecialistgroup.org).

Otters [Mustelidae Family] are poorly studied aquatic mammals. Our earlier studies have

documented otter populations in Sindhudurga district, Maharashtra. No comprehensive data for

the populations and current status of this taxon is available for the Ratnagiri district,

Maharashtra, India. The sporadic sightings are rare, mostly in and around mangroves and the

habitats are not easily accessible. In this scenario, focused studies such as the present study is

undertaken to obtain scientific data for the conservation of this species. The distribution of

Crocodile is poorly documented in coastal areas. Hence, this species was also surveyed.

The preliminary findings from the survey are presented in this report.

Study Area (Transects):

The surveys for otters and crocodiles were conducted in Mangrove patches in the coastal areas in

Ratnagiri district, Maharashtra. The creeks and backwaters and Minor Irrigation Tanks (MIT)

were also included in the surveys:

Objectives:

1. Document the diversity of otter and crocodile species in the study area.

2. Record the distribution and map the GPS coordinates.

3. Document the sites where otters and crocodile species are present.

4. Characterize habitat preference of otters and crocodile species.

5. Study the food preferences by field observations or prey remains.

6. Identify threats to otter and crocodile species.


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Number of visits and data analysis:

Total 14 visits were carried out during the period from April 2019 to November 2019 for the

study of otters and crocodiles in the Ratnagiri district.

Methodology for Otter and Crocodile Survey

FOLLOWING ASPECTS WERE CONSIDERED DURING SURVEYS:

1. Two seasons were covered (Summer and Monsoon).

2. Surveys were conducted from dawn to dusk.

3. Inclement weather was avoided for surveys and human disturbance was taken into

consideration.

4. Low density population species like otters are generally difficult to survey. Otter detection

needs skills that the researchers have acquired due to past experience particularly in Sindhudurga

district, and careful attention was paid to detect otter and crocodile activity during surveys.

CONSISTENCY OF SAMPLING:

1. Same methods were used and transects were conducted in each season.

2. Standard habitat codes were used for reporting.

3. GPS methodology was used to record otter and crocodile presence sites.

4. Same researchers conducted the surveys.

SPECIES IDENTIFICATION:

Species identification was done from photographs and / or pugmarks and comparing them with

diagnostic keys from published data.

SURVEY TECHNIQUES:

Observational study was done strictly as per the provisions of the WPA 1972. Field observations

were taken as follows:

For the crepuscular species like otters (small to medium sized aquatic mammals) a combination

of techniques were used as follows:.

1. Visual Creek/River Boat Transects by non-intersecting like transects from boats by sailing

along the tidal creeks, backwaters and rivers for each of the 12 creeks.


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2. Bank Line Transects –(ISU) for 600 m at 6 sites in each 10 km stretch. These six sites are

designated as the Intensive Search Units (ISU). GPS locations of sightings will be recorded for

all positive sites. Transects shall be made for each of the 12 creeks.

3. Under Bridge Surveys (because spraints/scats tend to stay longer in these areas as compared

to on open banks). GPS locations of otter sightings will be recorded.

4. Modified Scent Station Surveys: The prawn and crab farms in the study areas will be used as

modified scent stations. Such sites will be visited to find the presence or absence of otters. GPS

locations of otter sightings will be recorded.

5. Supplementary data from questionnaire response from local fishermen.

UNITS OF THE DATA:

1. Presence / Absence for study sites (tide, embankments, etc.).

2. Identification of otter and crocodile species.

3. Group composition.

4. Estimate of abundance.

5. Location of high density sightings.

OBSERVATIONS:

Estimate of Presence: This was done by pooling data from all the observations. Data is

tabulated creek-wise along with maps.

1. Diversity & Distribution:

1A .Diversity: The only species of otter in the mangrove habitats recorded during the

study was the Smooth-coated Otter Lutrogale perspicillata. The species of crocodile

recorded was Marsh Crocodile Crocodylus palustris.

1B. Distribution: Otter species was present in the 2 creeks surveyed. The otters inhabit

saline waters and were seen in the water or near mangroves. Crocodile was seen in one

creek and few MITanks.

2. Presence of otter sparints and otter sightings were important indicators of otter presence. GPS

coordinates of all survey sites including intensive survey units (ISU’s) were recorded. Otter

sparaints have distinct characteristic appearances due to their character and contents. Otter

sparaints are the most reliable indicators for the presence of otters. Otter sparaints are visible on

open banks along the creeks, on Kharland Scheme bunds and also on the coasts and MIT

embankments. However, they are not seen when the coasts are occupied by dense mangroves.

Crocodiles were seen on banks or in water. It needs experience to identify crocodiles swimming

in water.


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3. Under Bridge Surveys: Otter spraints are reliably seen under bridges where they remain for

a long time and old spariants could also be seen.

4. Otter sightings are relatively rare as compared to otter spraints. During the study a minimum

of 2 otters and otter groups between 9 to 12 individuals were observed. Crocodiles were seen as

individuals and small groups on banks and in water.

5. Otter spraint analysis shows fish, crab and mollusk remains.

6. Modified Scent Station Surveys: Otters were recorded in near crab and prawn farms.

7. Otters mostly exhibit crepuscular habits but also were recorded fishing and swimming during

the noon in our study. Otters were associated with mangrove habitats along the creeks and they

use mangroves for cover and resting.

8. Trap Camera Images: We shall try for otter pictures using trap cameras subsequently.

9. Threats: Otters were absent where habitat loss (urbanization of previous otter resting sites),

and human encroachment of natural habitats were noted.

10. Local Information: Information was locally obtained about occasional hunting of otters

using snares and bait traps. Otters are known to cause some damage to fishing nets and to crab

and prawn farms. But the fishermen community is tolerant of the otters.

11. Otters are generally well known among the fishing community and are called as Hud, Ood

and Uda in Marathi language. Crocodile is known as mugger.

12. Crocodiles were present in one creek. They were seen basking and we also recorded them

entering water when disturbed by our presence.


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Otter and Crocodile Survey

Shastri River and creek survey showing locality, coordinates and otter and crocodile presence

and absence data with populations

SN Locality LAT LONG Otter Crocodile

1 Gad River, Aravali 173171 735224 4 2

2 Kondiware-KT

Ware

173115 734906 15 5 Nest

3 Makhijan Bridge 172702 734953 5 3

4 Gowalwadi 172630 734850 0 2

5 Dhamapur 172422 734504 11 2; 1 adult

died

6 Karanjuve 172182 734290 4 8

7 Manjare Kharkund

Opposite Bank

172085 734300 4 0

8 Phungus Bridge 171705 734706 3 0

9 Konde Tembha

Datta Mandir

171610 734701 3 0

10 Rai Bhatgao Bridge 172087 734159 11 0

11 Medhe Shastri and

Sonawi

Confluence

172084 734125 12 0

12 Chave Kharland

Bund

171990 7338650 4 0

13 Deud Kharland

Bund

172152 733450 12 0

14 Agar-Naral

Shriram Nagar

Jetty

172261 733446 8 0

15 Kolisare Jetty 172367 733352 5 0

16 Gad-Naral 172550 733356 4 0


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17 Vaidya Lavgan 172635 733128 12 0

18 Chaferi Kharland

Scheme

172804 732538 11 0

19 Jaygad Sand Bar 172866 732533 10 0

Sangameshwar Creek Survey showing locality, coordinates and otter and crocodile presence

and absence data with populations


1 Nidhale Wadi

Maitri Park Hotel

171693 735114 12 0

2 Lowale 171540 735454 15 0

3 Shivane 171431 735500 40 0

4 Burambi Bridge,

Terye

171379 735651 25 0

5 Machure 171358 735395 24 0

6 Nhavyacha Doh,

Chowk

171335 735948 25 0

7 Kule Bridge,

Vashi-Kule

171639 736397 4 0

8 Shastri Bridge 171835 735458 5 0

Minor Irrigation Tanks (MIT), Ratnagiri District survey showing locality, coordinates

and otter and crocodile presence and absence data with populations


1 Morawane – MIT 175494 736000 1 0

2 Kolkawadi 174706 736444 2 0


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3 Talwat Khed-MIT 176456 736165 0 0

4 Khopi Shirgao-MIT 176726 735677 2 0

5 Natuwadi Medium

Project

178369 734004 2 0

6 Shirawali - MIT 177523 734300 2 0

8 Gadgadi Dam-MIT 171725 736537 5 0

7 Phanaswadi,

Kapsal, MIT

174845 735105 0 5

8 Guhagar MIT 174886 732205 0 2

9 Khopad M I tank 175413 734595 0 25

10 Kamathe M I tank 174856 735132 0 5

11 Kalwande M I tank 174792 734880 0 2

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Tambi,Malghar, M

I tank 174787 734450 0 20

13 Kalwande M I tank 174792 734880 0 2

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Tambi,Malghar, M

I tank 174787 734450 0 20


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Vasishthi River and Creek survey showing locality, coordinates and otter and crocodile

presence and absence data with populations

Sr. No Locality Lat. Lon. Otter

population Crocodile population

1 Chiplun, L Bank 17.53.95 N 73.52.25

E 12 3

2 Shiral, L Bank 17.53.63 N 73.47.76

E 10 5

3 Govalkot, L Bank. 0 0 0 10

4 Bhile, L Bank. 17.57.14 N 73.46.90

E 5 3

5 Karambavane, L Bank 17.57.94 N 73.41.85

E 5 3

6 Maldoli, L Bank 17.57.81 N 73.39.58

E 5 5

7 Gangrai, L Bank 17.57.02 N 73.38.14

E 2 3

8 Donavali, L Bank 17.56.20 N 73.36.60

E 3 1

9 Kaluste 175591 734780 4 2

10 Waghivare, Rt. Bank 175666 733525 4 6

11 Pedhe Parshuram, Rt Bank 175542 734870 8 8

12 Dhamandevi Rt. Bank 175585 734898 4 7

13 Kotavali Rt. Bank 175921 734415 4 8

14 Songao Rt. Bank 175776 734375 4 5


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Otters Shastri River/Creek

All are survey points

(Green - presence; Red - absence)

Otters Sanameshwar vicinity




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Otters recorded near Minor Irrigation Tanks (MIT)



Crocodiles in Shastri River / Creek




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Crocodiles in Sangameshwar vicinity



Crocodiles in Minor Irrigation Tanks (MIT)




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CONCLUSIONS

One otter species the Smooth-coated Otter Lutrogale perspicillata was recorded in the

mangrove habitats of Sindhudurga district, Maharashtra. Otter sightings are relatively rare.

Indirect evidence of otters was seen in the study area. Spraints are reliable indicators of otter

presence and they also reveal the type of food consumed by the otters. Otter spraint analysis

shows fish, crab and mollusk remains. Further studies will be undertaken to identify till generic

or specific level whenever possible.Otters mostly exhibit crepuscular habits, however we rarely

recorded them fishing and swimming during the noon. Otters use mangroves for cover and

resting.

Marsh Crocodile Crocodylus palustris was recorded during the survey. Crocodiles were present

in one creek (Vasishthi). They were seen basking or entering water when disturbed by human

presence.

Preliminary observations showed that threats to otters and crocodiles were habitat loss

(urbanization of previous otter resting sites), and human disturbance in natural habitats.

The otter and crocodile survey is ongoing and additional areas will be covered during later

months. The finding and further analysis will be conveyed in the subsequent report.

Thanking you,

Sincerely,

Dr. Satish Pande MD, DNB, PhD, FMASci., FLS

Director, Ela Foundation, Pune

[Email: [email protected]; Mobile: 09822193707].


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APPENDIX I

Photographs taken during the survey

One site of otter survey along the bund of Bhile Kharland development scheme of the

Government of Maharashtra. Typically water can be seen on both sides of the bund. The

otters use the bund for sun basking, spraint deposition and crossing over.

(Photo: Ram Mone, Ela Foundation, Pune)

A typical white colored otter spraint is composed of fish and crab remains. The size

of the spraint depends on the otter population using this latrine. An old spraint composed

of fish remains (below);

(Photo: Dr. Satish Pande, Ela Foundation, Pune)


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Crocodile recorded at Bhile.

(Photo: Ela Foundation, Pune)

Crocodile recorded at Gangrai.

(Photo: Ela Foundation, Pune)


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Crocodiles recorded at Khopad

Crocodile recorded at Chiplun

Garbage can be seen in this pond where crocodiles inhabit the water and banks

Ist Interim Report - mangroves.maharashtra.gov.in

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