bird assemblages in the thale noi non-hunting area ... · saha karn bhaet group, bangkok, thailand....
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Bird assemblages in the Thale Noi
non-hunting area, southern Thailand
Kua Rittiboon (Lecturer in Environmental Science, PSU)
Seminar: “Research Methods in Practice” KMIT Lad Krabang April 25-26 2013
We used factor analysis to classify assemblages of bird species
with respect to incidence by season and location. For 23 common
resident species in Thale Noi reserve in Pattalung province, we
found five groups that correlated with their habitats and availability
of food. Group 1 (7 species) was found in flooded habitats. Group
2 (6 species) was found in terrestrial habitats containing grain and
insects. Group 3 (6 species) was found in habitats connecting from
shallow fresh water to suburban environments and typically
providing insect food sources in water and on land. Group 4 (two
species) was found in similar habitats to that of the second group,
but related to fruit trees. Group 5 (two species) was found in
lowland habitats with dense undergrowth providing different food
types including insects, seeds and fruit, particularly figs. This
classification reflects bird behaviour rather than taxonomy.
2What is a resident bird?
“A species which is present throughout the year and presumed
to breed.” (Lekagul and Round: 2005)
3Study area
1. Khuan Kreng
2. Khuan Nang Whean
3. Khuan Thale Mong
4. Klong Yuan
5. Khuan Khi Sian
6. Ban Pran
7. Laem Din
4
5
Data collection
• The bird data were obtained from the office of Thale Noi non-hunting area.
• Data were collected monthly between 2004 and 2007, at seven locations.
• The bird surveys were conducted on the same day each month, at each locations.
• Species were identified using binoculars and field guide (Lekagul & Round 2005).
6Data management
• Resident bird classification
23 species
• Lekagul and Round (2005)
• Found every study year
• Median incidence rate per day greater than zero
•Time definition
4 Seasons of year
• Jan-Mar : 1st season
• Apr-Jun : 2nd season
• Jul -Sep : 3rd season
• Oct-Dec : 4th season
•Incidence rate
Numbers of birds sighted per day (7 hours)
7
Factor Analysis
• To allocate the 23 bird species into a smaller
number of interpretable groups that tended to
appear on the same occasions
• The incidence rates of the 23 species: variables of
interest
• Each variables has 112 observations
(4 seasons x 4 years x 7 sites)
8Results of factor analysis
• Factor 1
• Factor 2
• Factor 3
• Factor 4
• Factor 5
9
Factor 1• Wetland
habitats (freshwater,marsh and shallow water);
• Providing aquatic plants;
• Identified ahabitat providing continuous flood and aquatic plants.
10
Factor 2
• Mostly land birds
• Terrestrial habitat
• Feeding on a variety of foods
• Greater Coucal,Spotted Dove & Cattle Egret
• Foraging on
ground
• Black Drongo: agriculture & insects.
• Identified terrestrial habitat; grain and insects.
11
• Wide range
of habitats.
• Freshwater, woodland, human habitat.
• Purple Heron feeds mainly on fish.
• Common Myna: urban & suburban environment.
• Little Egret, Black-winged Stilt: aquatic insects.
• Common Tailorbird, Barn Swallow actively forage on insects.
• Identified habitat connecting freshwater to suburban
environment, food sources on land and in water.
Factor 3
• freshwater marsh, denseundergrowth.
Forages on theground, feeds mainly on seeds, insects and small fish.
12
Factor 4
Factor 5
• Land birds• Open woodland to human habitat; fond of fruit.
• Lowland forest;Fig-eating specialist.
Conclusions13
• Factor analysis - groups of birds that reflect their
behaviours rather than their taxonomies.
• Habitat attributes and food types associated with the
occurrence of groups of resident birds.
• Birds in the same groups respond to their existence
in different proportions of vertical strata.
• Niche segregation enables these species to coexist in
the same habitat (Kwok, 2009).
ReferencesLekagul B and PD Round (2005). A guide to the birds of Thailand,
Saha Karn Bhaet Group, Bangkok, Thailand. 457 pp.
Kwok HK (2009). Foraging ecology of insectivorous birds in a mixed
forest of Hong Kong. Acta Ecologica Sinica. 29(6): 341-346.