Wintering Population of Four Migratory Species of Waders in the Gulf Of

Wintering population of four migratory speciesof waders in the Gulf of Kachchh and human pressures

V. J. Bhuva & V. C. Soni

BhuvaV. J. andSoni V. C. 1998.Wintering population of four migratoryspecies of wadersin the Gulf of Kachchhand human pressures. Wader Study Group Bull. 86:48 -51.

The numberof CrabPlover Dromas ardeola, Curlew Numenius arquata, Black-tailed Godwit Limosa limosa and Avocet Recurvirostra avosettaare described for twostudy areas, in theGulf of Kachchh,Narara island and Rozybundar coast, where salt-works, sand-banks andmudflats are important for birdsfor roosting,especially during high tide. Theseroosting areas are threatened by humanactivities.

V.J. Bhuva,V. C. Soni,Department of Biosciences,Saurashtra University, Rajkot'- 360 005, Gujarat,India.

INTRODUCTION 1994). In the Gulf, humanactivities have increased greatly. The Gulf of Kachchhis designatedas a Marine NationalPark Fishingappears to havelittle effect on the bird life in the area part of whichis locatedat the northof the Saurashtrapeninsula but industrialdevelopment threatens both the roostingand in theJamnagar district, Gujarat, India. The longcoastline, of foragingsites. Ship repairingworks and the constructionof which it is a part, consistsof broadintertidal mudflats, coral the concretejetty on Rozybundarare currentlycausing much reefs,sandy and rocky beaches. It offersa greatdiversity of disturbance to the birds. habitatsfor birdsto utilize,and is veryrich in boththe variety andnumber of migratoryand resident birds. The Gulf of STUDY AREAS Kachchh,however, has been relatively less well studiedthan The Gulf of Kachchhhas an areaof approximately7,350 km2 otherareas and little publishedmaterial exists (Ali 1945; anda maximumdepth of about60 m (Hashimiet al. 1978). Abdulali 1962,1963;Himmatsinhji 1968; Parasharya 1984; Inshore in the Marine National Park, however, the maximum Palmes& Briggs 1986; Naik et al. 1991; Mundkur 1991). depthdoes not exceed25 m. The Gulf of Kachchhstretches from 69o 05' E at the entranceto 70ø 20' E at the end (Figure1). In total, 86 bird specieshave been recorded in the salt-works, The averagetidal rangeis 4 m with a tidal velocityof 2-5 and80 specieson the islandsand coast along the Gulf (Naik et knots. al. 1991). Many speciesfound in the Gulf as well as in the salt-worksare common.This studydeals with four wader NararaIsland is situated60 km westfrom Jamnagarand is species;Crab Plover Drornasardeola, Curlew Numenius very small,with a lengthof 0.5 km andwidth of 40 - 50 m arquata,Black-tailed Godwit Limosalimosa and Avocet duringhigh tide (Figure2). Duringlow tide,up to 2 km of the Recurvirostra avosetta. intertidalarea are exposed, comprising mainly rocky and sandy habitatsand smallmudflats. Rozybundaris situated10 km The Gulf of Kachchhincluding the Marine NationalPark and north-westof Jamnagarand also has a 2 km longintertidal area Sanctuaryis usedfor fishing,pearl and marine product whichis chieflymudflats with some rockyand sandy areas collection,industries, water transport and recreation (Singh (Figure 3).

MATERIALS AND METHODS Nararaisland and Narara salt-works, and Rozybundar coast and Rozybundarsalt-works will, from now on, be referredto as 23 ø Nararaisland and Rozybundar respectively. The studywas cardedout during 1991-92 and 1993-94. Data were collected by direct visualcounts. Observationswere cardedout oncea Gulf of Kachchh month,and the surveyscovered the entireNarara islandand •3 NararaIsland Rozybundar.Observations were recordedduring high tide as Rozybundar the birdswere foundroosting more compactlyat that time. Observationswere madeusing a x30-x45 telescopeand 8x30 binoculars.

RESULTS The roostingbehaviour of Crab Plover and Curlew were Figure 1. locationof studysites in the Gulf of Kachh. completelydependent on the tidal cycle. Crab Ploversroosted 49

Lighthouse 22o34 ' ß oø 22030; Ship Repairing Works N øø• IntertidalZone t ß Intertidal Zone t o, o Narara Island

IntertidalZone

Jetty

Saltworks Saltworks

Saltworks 69o40 ' '"' Saltworks, Figure 2. NararaIslandIntertidal and Zsurrounding area. •',,, 22ø: togetherat sitesalong or closeto the southwestcoast, and Curlewsroosted together on mudflatsof the eastcoast of Narara island.

Crab Plover Figure4 showsthe averagepopulation of CrabPlovers on To Jamnagar Nararaisland was 771 +_174.69 and on Rozybundar86.5+ 14.31. The averageCrab Plover population was about nine 70o02 ' timeshigher at Nararaisland compared with thatof Figure 3. Rozybundarand surroundingarea. Rozybundarthroughout the winter. Overall,the CrabPlover populationreached its peakin Decemberand January. Curlew The Curlewpopulation was alsohigher on Nararaisland (Figure5). In winter,the averagepopulation of Curlewson Nararaisland was aboutten timeshigher (112.25 + 56.16) than 891 894 1 Narara thatof Rozybundar(11.75 +_4.38). The highestnumber of 827 !--I Rozybundar Curlewsrecorded at Narara Island in Januarywas 209 but only 16 at Rozybundarin December- January. 700. 600 472 500 2O9 1 Narara 200 ß 300 !--I Rozybundar z 100 70

November December January February 89 73 78 month Figure 4. Averagenumber of Crabplover at Nararaand Rozybundar. 50"

0 November December January February month

Figure 5. Averagenumber of Curlew at Nararaand Rozybundar. 50

Black-tailed Godwit DISCUSSION In winter,the averagepopulation of Black-tailedGodwits on Winter migratorywader populations are governedby three Nararaisland was 247.25 + 39.75 whichwas three times higher factors,namely temperature; human disturbance and thanthat of Rozybundarwhere the averagepopulation was availabilityof prey. Temperatureand prey availabilityare 75.25 + 28.86. Figure 6 showsthat numbers were higherin naturalfactors but the bird populationin the studyarea is Decemberand Januaryat both sites. greatlyaffected by constantlyincreasing human interference.

This comparisonof the populationsof the four mostabundant 1 Narara speciesshows higher concentrations at Nararaisland than on 292 Rozybundar,which we believeis dueto Rozybundarsite 300 281 [• Rozybundar sufferingmore from humandisturbance. • 250 o 215 On Nararaisland, human activity is mainly restrictedto a few 201 fishermenwho work acrossthe intertidalarea during the ebb -o 200 tide. Oil tankersanchor far off- shoreto emptycrude oil; this -• 150 reachesthe mainlandthrough a pipelinewhich does not cause any disturbanceto birds. Narara Islandis usedfor Nature (o100 EducationCamps arranged by the ForestDepartment of GujaratState during winter, but campactivities are limited to o (5 50 birdwatchingand the studyof marineorganisms. z 0 On Rozybundar,on the otherhand, human activity is November December January February comparativelyhigh and causingmuch disturbance to birdsand month has increased since 1991. Fishermen stake out nets across the Figure 6. Averagenumber of Black-tailedGodwit at Nararaand Rozybundar. mudflatin the ebbtide. Shiprepairing works, situated on the easternside of the concretewalkway are closeto the high Avocet water mark and cause noise which scares the birds. Parallel to Figure 7 showsthe winter populationof Avocetsat Narara thewest side of the concretewalkway, a big concretejetty is islandand Rozybundar.The averagepopulation of Avocets also under construction. These activities are on sites used as was 136.75 + 84.38 on Narara island and 60.25 _+35.35 on roosts and thus affect the birds. Rozybundar,i.e. more thantwice as high at the formersite. As with the otherthree species, the highestcounts were recorded in Decemberand Januaryat both sites. CONCLUSION There were significantdifferences between the populationson For the conservationof waders in the Gulf of Kachchh, it is essentialto protectthe major roostingareas, particularly those usedduring high tide by the residentas well aswintering bird 250 231 1 Narara populations.Further, several industrial concerns are going to 204 N Rozybundar build in theseareas and, if not restricted,are goingto makethe 200' areainhospitable for birds.

ACKNOWLEDGMENTS We thankthe Head, Departmentof Biosciences,Saurashtra 103 University,for encouragement.We are alsograteful to the 74 Directorand staff of the Marine NationalPark, Jamnagar, for permissionto carryout work in the Park. z 50 35

o REFERENCES November December January February Ali, S. 1995. TheBirds of Kutch.Oxford UniversityPress, Bombay. month Abdulali,H. 1962.An ornithologicaltrip to the Gulf of Kutch.J. Bombaynat Figure 7. Averagenumber of Avocetat Nararaand Rozybundar. Hist. Soc. 59: 655-658.

NararaIsland and those on Rozybundarin all monthsexcept Abdulali,H. 1963.Ornithological notes of a secondtrip to the Gulf of KutchJ. November,December and February for Curlew andFebruary Bombaynat. Hist. Soc. 60: 703-708. for Crab Plover. Hashimi, N.H., Nair, R. R. and Kidwai, R. M. 1978. Sedimentsof the Gulf of Kutch - a high energytide dominatedenvironment. Indian J. Mar. Sci. 7: 1-7

Himmatsinhji,M. K. 1968. Someinteresting migrants in Kutch.J. Bombay nat. Hist. Soc. 65: 225. 51

Mundkur,T. 1991.Nesting and feeding ecology of aquaticbirds in Saurashtra Parasharya,B. M. 1984.Studies on the coastalbirds and their marinehabitat, and Gulf of Kachchh.Ph.D. thesis,Saurashtra University, Rajkot. withspecial emphasis on thebiology of theIndian Reef Heron Egretta gularis. Ph.D. thesis,Saurashtra University, Rajkot. Naik, R. M., Murthy,M.S., Mansuri,A. P., Rao,Y. N., Pravez,R., Mundkur, T., Krishnan,S., Faldu,P. J. and Krishna,T. S. V. R. 1991. Studieson coastal Singh,H. S. 1994.Management Plan, MarineNational Park, Jamnagar,India. marineecosystems and anthropogenic pressure in the Gulf of Kachchh.Final report,submitted to WorldWide Fund for Nature- India.

Palmes,P. andBriggs, C. 1986.Crab Plovers Dromas ardeola in theGulf of Kutch. Forktail 1 ß 21-28.