SPATIAL FIN-FISHERY SPECIES DIVERSITY OF ULHAS RIVER

ESTUARY

Rathod Sudesh D.1 and Dr. Nandini Patil

2

Department of Zoology, B. N. Bandodkar College of Science, Thane, Maharashtra, India

ABSTRACT

Ulhas river estuary is subjected to heavy pollution due to the industrial and residential belts established

along its either banks incurring huge amount of non-point and point pollution sources. Ambient

hydrological conditions assessed during July 2005 to May 2006 and anthropogenic stresses are critical

therefore leading to the decline in the fishery diversity as compared to earlier records. The abundant main

fin-fishery species were replaced by the pollution tolerant species in due course of time. Several fin-

fisheries have been obliterated in the estuary. Majority of the fishermen have abandoned the fishing

practices due to non-productive status of the Ulhas river estuary fin-fisheries. The species diversity and

species richness of the present diversity were conducive of the former observations.

Keywords: Ulhas river estuary, fin-fish, diversity, fisheries

Oral Presentation at Biodiversity Asia-2012, Bangalore, India……..

International conference

Biodiversity Asia 2012- Science, Policy and Governance

2nd Regional Conference of Society for Conservation of Biology- Asia

Indian Institute of Science, Bangalore

7-10, August 2012,

Go to: www.biodiversityasia2012.org

Rathod Sudesh D. and Dr. Nandini Patil

Department of Zoology, B. N. Bandodkar

College of Science, Thane, Maharashtra, India

Study Area

Ulhas river estuary (URE) leis in the vicinity of Thane city, Maharashtra State, India (between the latitude 18° 45’to19°19’, N and longitude 73°21’to72° 45’, E on the world map)

Methodology

Three zones of Ulhas River Estuary (URE)

viz. Z-I; Z-II & Z-III

Study from July 2005 to May 2006 (11

months)

Hydrology

WT, LP, SS, pH, Salinity, DO, BOD, PO4-P

& NO3-N

Anthropogenic activities at sight

Fishery catch survey survey at sight &

markets

Fish Landing

Fishing Gears and Crafts

Mudskipper Fishing & Dragnet (Bari)

Hand Picking

Mudskipper Fishing

‘Bari’

Barrier Net (Vana); (Pocha); Bag Net (Bokshi)

Gillnet (Busa)

‘Vana’

‘Bokshi’

‘Pocha’Gillnet

Hand Nets & Others

Seed’s net ‘Jholva’- Waddingnet

‘Fug’ – Cast net Lift Net

Mechanized Boat – ‘Padava’ & Canoe ‘Hodi’

Padava

Result – Zonal Hydrology

27.0

27.2

27.4

27.6

27.8

28.0

28.2

28.4

Z-I Z-II Z-III

Water Temp (oC)

0.00

5.00

10.00

15.00

20.00

25.00

Z-I Z-II Z-III

Light Penetration (cm)

0.00

2.00

4.00

6.00

8.00

10.00

12.00

Z-I Z-II Z-III

Suspended Solids (gm/l)

7.40

7.45

7.50

7.55

7.60

7.65

7.70

7.75

7.80

7.85

Z-I Z-II Z-III

pH

Zonal Hydrology

0.00

5.00

10.00

15.00

20.00

25.00

Z-I Z-II Z-III

Salinity (ppt)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

Z-I Z-II Z-III

DO (mg/l)

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

Z-I Z-II Z-III

BOD (mg/l)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

Z-I Z-II Z-III

PO4-P (mg/l)

Very High

SS, BOD, PO4-

P, NO3-N and

hypoxia indicate high

pollution status of the

ambient environment

Z-I is highly polluted

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

Z-I Z-II Z-III

NO3-N (mg/l)

Impact of Anthropogenic Activities

Civil & Ritual Activities

Solid Waste Dumping

Sand Excavation

Boats engaged in sand excavation by ‘Dubi’ method

Mangrove Extraction and Boat Building

Zonal Intensity of Anthropogenic

Perturbation

0

2

4

6

8

10

12

14

16

Z-I Z-II Z-III

Solid waste

Sewage/effluent

Civil activities

Sand excavation

Sand landing

Fishing attempts intensity

0

20

40

60

80

100

120

Z-I Z-II Z-III

Zonal Ave Fishing Intensity

Vana

Dol

Bari

Gobiids

HdLine

Gillnets

Species Succession

Hardy species like Mystus gulio, Mugil spp., Therapon

spp., Scylla serrata, Boleophthalmus dussumieri still persist in

Zone-I of the URE

Succession of species such as Oreochromis

mossambicus, Megalops cyprinoides etc. occurred with the

advent of pollution status.

Zonal Fin Fisheries Zonal Catch & Diversity

5250 6981 8656

0

5

10

15

20

25

30

35

40

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

Z-I Z-II Z-III

Spp. Diversity

Ave. Landing (kg)

Repercussions of Anthropogenic

Activities: Mangrove siccession

Acanthus ilicifolius

Mangrove

Plastic masking pneumatophores

Repercussions of Anthropogenic

Activities: Fish

Fish Mass-killMudskipper youngones trapped in plastic

Socio-economic Impact

AFP: Actual fishermen population

FPF: Fishermen presently practicing the fishing

9000

4500

8500

438194

653

0

1

2

3

4

5

6

7

8

9

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

Z-I Z-II Z-III

AFP

FPF

%

Conclusion

Health of ambient water deteriorates with human

interferences, causing mass kill and eradication of

several species from the URE.

Fin-Fisheries assemblage and diversity declined with

increase in anthropogenic perturbation as evident from

fisheries of Zone-I and Zone-II are low. Zone-I, almost

has become non-productive

With the decline in fisheries fishing activities declined.

Major population fishermen abandoned fishing

Practice.

Acknowledgement

We are grateful to our Principal, B. N. Bandodkar

College of Science for allowing us to present the

paper.

We are indebted to organizing body of the

Conference ‘Biodiversity Asia 2012: Science, Policy

& Governance’ for allowing us to present our work.

We also express our thanks to those all who have

extended their hands in preparation of this

presentation.

Thank You