Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak

Labuanium politum is an obligate arboreal crab that inhabits the nipah palm tree population in the mangrove area. L. politum also locally known as `Geramak Apong'. This crab is nocturnal species. Morphological descriptions and population structure of L. politum were studied on 17 September 20...

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Main Author: Akma Iddin, Masini
Format: Final Year Project Report / IMRAD
Language:English
English
Published: Universiti Malaysia Sarawak, (UNIMAS) 2016
Subjects:
Online Access:http://ir.unimas.my/id/eprint/15464/
http://ir.unimas.my/id/eprint/15464/3/AKMA%20IDDIN%20BIN%20MASINI%2024pgs.pdf
http://ir.unimas.my/id/eprint/15464/6/Arin%20Vynona%20Robert%20ft.pdf
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author Akma Iddin, Masini
author_facet Akma Iddin, Masini
author_sort Akma Iddin, Masini
building UNIMAS Institutional Repository
collection Online Access
description Labuanium politum is an obligate arboreal crab that inhabits the nipah palm tree population in the mangrove area. L. politum also locally known as `Geramak Apong'. This crab is nocturnal species. Morphological descriptions and population structure of L. politum were studied on 17 September 2015 at Kampung Tanjong Assam, Spaoh. Meanwhile, the captivity behaviour study was also conducted on 23 March 2016 at Kampung Tanjong Assam, Spoah. These crabs were caught using a special hook. Samplings covered six plots that involved disturbed and undisturbed area. Eleven samples have been kept alive in a plastic container and two samples also kept in an aquarium to observe their behaviour in captivity. This crab exhibited with squarish carapace, same size of chela and reddish brown in colour. The range size of L. politum collected was from 17.53 mm - 35.99 mm for carapace width (CW) and 19.54 mm - 40.10 mm for carapace length (CL). The size of an egg is approximately 330 μm. The population of L. politum were documented higher in undisturbed area compared to disturbed area. The findings indicated that male crabs found were bigger in size class compared to female. The mean of carapace size (CW and CL) of L. politum showed bigger size in undisturbed area compared to disturbed area and the statistical analysis (2 sample independent t-test, p= 0.05) showed significant differences in the mean size of carapace. The findings of the studies also indicated that the size of males dominated the biggest size class which at range class size 38 mm - 41 mm. The sex ratios of L. politum documented mostly were skewed towards female and 20 % of the females were found berried. The overall evaluation based on densities indicates that Kampung Tanjong Assam populations of L. politum declining caused by exploitation from local people. The sex ratio was reported skewed towards female that might related to densities of nipah palm tree and territorial behaviour of male crabs.
first_indexed 2025-11-15T06:46:21Z
format Final Year Project Report / IMRAD
id unimas-15464
institution Universiti Malaysia Sarawak
institution_category Local University
language English
English
last_indexed 2025-11-15T06:46:21Z
publishDate 2016
publisher Universiti Malaysia Sarawak, (UNIMAS)
recordtype eprints
repository_type Digital Repository
spelling unimas-154642023-08-21T07:49:50Z http://ir.unimas.my/id/eprint/15464/ Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak Akma Iddin, Masini SH Aquaculture. Fisheries. Angling Labuanium politum is an obligate arboreal crab that inhabits the nipah palm tree population in the mangrove area. L. politum also locally known as `Geramak Apong'. This crab is nocturnal species. Morphological descriptions and population structure of L. politum were studied on 17 September 2015 at Kampung Tanjong Assam, Spaoh. Meanwhile, the captivity behaviour study was also conducted on 23 March 2016 at Kampung Tanjong Assam, Spoah. These crabs were caught using a special hook. Samplings covered six plots that involved disturbed and undisturbed area. Eleven samples have been kept alive in a plastic container and two samples also kept in an aquarium to observe their behaviour in captivity. This crab exhibited with squarish carapace, same size of chela and reddish brown in colour. The range size of L. politum collected was from 17.53 mm - 35.99 mm for carapace width (CW) and 19.54 mm - 40.10 mm for carapace length (CL). The size of an egg is approximately 330 μm. The population of L. politum were documented higher in undisturbed area compared to disturbed area. The findings indicated that male crabs found were bigger in size class compared to female. The mean of carapace size (CW and CL) of L. politum showed bigger size in undisturbed area compared to disturbed area and the statistical analysis (2 sample independent t-test, p= 0.05) showed significant differences in the mean size of carapace. The findings of the studies also indicated that the size of males dominated the biggest size class which at range class size 38 mm - 41 mm. The sex ratios of L. politum documented mostly were skewed towards female and 20 % of the females were found berried. The overall evaluation based on densities indicates that Kampung Tanjong Assam populations of L. politum declining caused by exploitation from local people. The sex ratio was reported skewed towards female that might related to densities of nipah palm tree and territorial behaviour of male crabs. Universiti Malaysia Sarawak, (UNIMAS) 2016 Final Year Project Report / IMRAD NonPeerReviewed text en http://ir.unimas.my/id/eprint/15464/3/AKMA%20IDDIN%20BIN%20MASINI%2024pgs.pdf text en http://ir.unimas.my/id/eprint/15464/6/Arin%20Vynona%20Robert%20ft.pdf Akma Iddin, Masini (2016) Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak. [Final Year Project Report / IMRAD] (Unpublished)
spellingShingle SH Aquaculture. Fisheries. Angling
Akma Iddin, Masini
Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title_full Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title_fullStr Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title_full_unstemmed Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title_short Morphological description and population structure of an obligate arboreal crab (Labuanium politum) at Kampung Tanjong Assam, Spaoh, Sarawak
title_sort morphological description and population structure of an obligate arboreal crab (labuanium politum) at kampung tanjong assam, spaoh, sarawak
topic SH Aquaculture. Fisheries. Angling
url http://ir.unimas.my/id/eprint/15464/
http://ir.unimas.my/id/eprint/15464/3/AKMA%20IDDIN%20BIN%20MASINI%2024pgs.pdf
http://ir.unimas.my/id/eprint/15464/6/Arin%20Vynona%20Robert%20ft.pdf