Birds Communities at Mangrove of Batu Ampar , Kubu Raya District , West Kalimantan Province

Batu Ampar mangrove is an important bird habitat especially for birds which have relation to mangrove ecosystem in West Kalimantan. The research was conducted in February to March 2007, at mangrove Batu Ampar demo site. Sampling was done to get representative area for bird survey. The 19 transects were chosen as sampling site to collect bird data such as species and number of individual. Bird surveys were carried out using Reconnaissance method and IPA (Index Point of Abundance) count method. The length of each transect was approximately 500 m. The results showed that the bird community's structure dominated by insectivorous birds represented approximately 60 % of total bird's species at mangrove Batu Ampar demo site. The abundance numbers of the individual with the bird's species has relation pattern like J opposite. Percentage of dominant bird species was approximately 11 %, those are such as stork billed kingfisher, white-collared kingfisher, common iora, chestnuts-rumped babbler, Strip-Tit Babbler, magpie robin, ashy tailorbird, mangrove blue flycatcher, pied fantail, mangrove whistler, Brown-throated Sunbird and Cooper-Throated Sunbird. Vertical structure of mangrove vegetation was used by birds at mangrove Batu Ampar demo site is mainly B stratum, and it used around 60 % birds species. Based on dendrogram analysis there were 5 cluster birds species. The mangrove bird specialists found at sampling area were mangrove blue flycatcher and Cooper throated sunbird.


Introduction
Mangrove Batu Ampar covers an area of approximately 14.050 ha and it is one of Kapuas River estuarine ecosystem.Batu Ampar mangrove is natural mangrove which it occurs at Kubu Raya district formerly was Pontianak District, West Kalimantan province.The mangrove is a unique ecosystem and fragile, it presents both ecosystem terrestrial and brackish water.But the mangrove has an important function on such as nursery ground, spawning ground, and habitat of wildlife include the bird.
Besides for bird's habitat, mangrove Batu Ampar has the social and economical function for people who live surrounding the area.Local people used mangrove for many purposes such as chips, charcoal, and for fish pond.If the mangroves are not well managed, it will cause a decrease both in the quality and quantity of mangrove as well as the bird's habitat.
Few studies on mangrove birds have been done in Indonesia, Malaysia, and Singapore (e.g.McClure & Husain 1968;Nisbet 1968;van Balen 1989;Noske 1995;Elfidasari 2006).Up to now there are still lacks of data on mangrove biodiversity, especially which emphasize bird diversity.Meanwhile, mangrove Batu Ampar as one of mangrove demo site in Indonesia.The conservation management of the demo site need basic information like birds diversity must be collected soon by guided research.
The objective of study aimed at obtaining data and information on bird diversity and habitat used by bird species concerning composition and structure of mangrove vegetation.
The demo site area is estuarine of Kapuas River.There are many streams that originate on the low hills and drain the project area to the nearby Batu Ampar bay.Besides Kapuas river, several river flows be caused many delta presents at the area such as Keluang river, Kemuning, Sepada, Bunbun dan Seruat river.The drainage patterns perform dendrite flow and it unique with the delta.
The climate at the project area is tropical with unclear a distinct between dry season and wet season, but less precipitation between June and July (Figure 1).The total average annual rainfall is 3,887 mm, the average temperature is 28.5 ºC and The average humidity around 89%.
Sediment alluvial soil covered almost dominated at the demo site project area.Physically, the solum is quite deep, and the chemist character is fertile.The mangrove dominated by tumu (Bruguiera gymnorhiza), bakau (Rhizophora apiculata,), and nipah (Nypha fruticans).
Observation Procedure Birds surveys were used Reconnaissance method and IPA (Index Point of Abundance) count method.Nineteen transects were made as mentioned above, with the length of each transect around 500 m.Data collections started every morning at 07.00 a.m. and lasted until 09.00 a.m.The counting of individual numbers was based on direct visual contact or the bird calls.The shape of sample for IPA method can be seen in Figure 2.

Results and Discussion
Bird Species Richness Based on field observation there were 57 species of birds at mangrove Batu Ampar demo site.The species richness was classified as medium (Adil et al. 2010, Elfidasari 2006, Jumilawaty 2011, Mardiastuti 1992, Mustari 1992, Widodo et. al. 1996).The birds attribute were found 2 species of bird is mangrove specialist, 4 species are birds migratory, 2 species waders, 1 species migratory raptor.Meanwhile, 15 species protected birds in Indonesia were found used mangrove as their habitat.The total number of bird species found at the demo site area was recorded in Table 1.The higher number of bird species is at mangrove primer habitat.The number bird species have influenced by mangrove vegetation such as composition and strata of mangrove canopy and mudflat area (Adil et al. 2010, Elfidasari 2006, Jumilawaty 2011, Baker et al. 2002, Lambert & Collar 2002, Lane et all 2011, Nisbet 1968, Noske 1995, Noske 1996. Sodhi et al. 1997, van Balen 1989, Widodo et al. 1996).

Structure of Bird
CommunityThe structure of bird communities at mangrove Batu Ampar demo site can be seen from the trophic level or bird guild.The bird guild at the project area is recorded in Table 2.The dominant guild at sample plot was insectivore approximately 60 % of bird community at mangrove ecosystem.This phenomenon was similar to some observations at other mangrove ecosystems that insectivore's bird was dominant (Adil et al. 2010, Elfidasari 2006, Jumilawaty 2011, Mustari 1992, Nisbet 1968, Noske 1995, Sodhi et al. 1997).Van Balen (1989) also mentioned that the mangrove in Java of insectivores and nectarivores birds was dominant.The smallest number species at the mangrove is mollusk & anthropod feeder and nectarivores bird around 2 % of bird community.

Birds Diversity and Evenness
The bird species diversity at the mangrove project area classified as moderate.The value of Shannon-Wiener Index Diversity was 1.68-2.91.Meanwhile, the evenness index bids species is 0.83-0.96.The highest diversity index was at Selat She sample plot and the smallest was at Sungai Kemuning Hulu.The species diversity and evenness classified as moderate (Adil et al. 2010, Elfidasari 2006, Jumilawaty 2011;Mustari 1992).
According to Hernowo (2005), the factors have influenced to bird species diversity in the forest which was high variation species vegetation, the number of forest layer and least disturbed areas.

Abundance and local distribution
The relation between species and the individual number of the bird at mangrove Batu Ampar demo site is J pattern reverse (Figure 4).This phenomenon is common in tropical rain forest area.Only five species are as abundance bird (D > 50 individuals) i.e brown-throated sunbird (A.malacensis), common iora (Aegithina tiphia), cooper throated sunbird (N.calcostetha), mangrove blue flycatcher (C.rufigastra) and ashy tailorbird (Orthotomus ruficeps).Besides those birds are abundance species, they are also having local distribution spread all of the sample area.Noske (1995) mentioned that ashy tailorbird was the most abundant species at each of the census sites in mangrove Peninsula of Malaysia.Meanwhile, birds species which have abundance are moderate (50 ind > D > 20 ind) such as magpie robin (Copsychus saularis), pied fantail (R. javanica), white collared kingfisher (H.chloris), chestnuts rumped babbler (Stachyris maculata) and mangrove whistler (Pachycephala grisola).The remaining bird species in the Figure 4, are as considered rare.

Similarity of Bird Communities at Batu Ampar Mangrove Demo Site
Based on dendrogram analysis (Figure 5), there are 5 group clusters birds communities at mangrove Batu Ampar demo site.The first cluster is groups species of birds present at mangrove of Sungai Kemuning hilir, Teluk Air, Pulau Dabung, Sungai Kemuning hulu, Sungai keluang and Ecotone Gunung Terjun with similarity index approximately 75 %, but second cluster is occur at mangrove of Selat Perling, Pulau tiga, Sungai Sepadan kiri, and Gunung Radak of 78 %.
Meanwhile the third cluster bird communities is birds occur at mangrove of Pulau Panjang 4, Pulau Panjang 2, and Gunung Terjun of 80 % and the fourth cluster is bird communities which live at mangrove of Nypah Panjang, Selat Sheh, and Bun-bun of 70 % similarity index, but the fifth cluster is birds communities present at mangrove of Pulau Burung, and Sungai Seruat approximately 65 %.

Mangrove strata used by Bird Communities
Based on field observation the mangrove habitat can be divided into three layer strata such as stratum A is mangrove habitat at Figure 3 Chart diagram of birds species diversity and evenness at Batu Ampar mangrove demo site.space up 10 m high, but B stratum is mangrove habitat at spaced 5 -10 m and stratum C at space below 5 m until forest floor.The results showed that stratum B is preferred by many bird species.The strata used were rather similar with Noske's observation (Noske 1995) that the bird foraging high at mangrove in Malaysia was significant used high at 2-8 m.Several examples of vertical habitat space was used by birds were reported as bellow.
Mangrove logged over forest is condition space of wood density, strata B still be used by 60 % birds species (Figure 9).The bird's species used such as common iora, ashy tailordbird, mangrove whistler, pied fantail, chestnut rumped babbler and sitta nutchad.

Conclusion
Mangrove Batu Ampar demo site has moderate bird diversity (H = 1.68 -2.91) and the evenness (E = 83 -0.96).Fifty-seven (57) species of birds have been identified occur at the mangrove area, including two species of mangrove i.e, mangrove blue flycatcher and cooper throated sunbird present.The bird community structure based on guild analysis showed that insectivorous birds represented approximately 60 % of total bird species at mangrove Batu Ampar demo site and the number of species was around 13 % from total bird species occurred at project area.The abundance between numbers of individual with the birds species have relation pattern like J opposite.The percentage of dominant bird species was around 11 %, those are such as stork billed kingfisher (P.capensis), white collared kingfisher (H.chloris), common iora (A.tiphia), chestnuts rumped babbler (S. maculata), strip tit babbler (Macronous gularis), magpie robin (C.saularis), ashy tailorbird (O.ruficeps), mangrove blue flycatcher (C.rufigastra), pied fantail (R. javanica), mangrove whistler (P.grisola), brown throated sunbird (A.malacensis) and cooper throated sunbird (N.calcostetha).Vertical structure of mangrove vegetation was used by birds at mangrove Batu Ampar demo site mantly is B stratum, and it be used around 60 % birds species.Base on dendrogram analysis occur 5 cluster birds species.

Figure 1
Figure 1 Sampling site at demo site mangrove Batu Ampar.

Figure 4
Figure 4 Chart diagram of relation between individual number and birds species at mangrove Batu Ampar demo site.

Figure 5
Figure5Dendrogram of bird communities at mangrove Batu Ampar demo site.Variables

Figure 6
Figure 6 Mangrove strata was used by birds at ecotone between mangrove and lowland tropical rain forest.

Figure 7
Figure 7 Mangrove strata was used by birds at shore area where present madflat area.

Figure 8
Figure 8 Mangrove strata was used by birds at good forest condition.

Figure 9
Figure 9 Mangrove strata was used by birds at logged over forest with space condition.

Figure 10
Figure 10 Mangrove strata was used by birds at mudflat area.

Table 1
Species birds richness at mangrove Batu Ampar demo site