Roads that dissect natural habitats present risks to wildlife, creating gaps or barriers which animals have to traverse in order to move within and between their habitats. Restoring habitat connectivity can be achieved naturally by planting trees and vines to reconnect forest gaps, or artificially by creating culverts for small ground vertebrates, building overpasses for large terrestrial animals, or installing canopy bridges for arboreal fauna. The 3-km Old Upper Thomson Road borders the eastern side of the Central Catchment Nature Reserve, the largest nature reserve in Singapore, and isolates it from neighbouring forest patches. To facilitate safe crossing for tree-dwelling animals such as the critically endangered Raffles’ banded langurs (Presbytis femoralis) along Old Upper Thomson Road, two rope bridges were installed. We monitored the use of these rope bridges by vertebrates from April 2020 to August 2021 through surveillance cameras attached on one end of each bridge. A total of 64 118 videos were processed, with 6218 (9.70%) containing vertebrates. Seven species, including three primates, two squirrels and two reptiles, utilised the bridges to travel between the forests. In particular, Raffles’ banded langurs made a total of 293 successful crossings. We have shown that these rope bridges are useful for arboreal species and can complement national efforts to restore connectivity in fragmented habitats.
The introduction of exotic species can have detrimental effects on local populations via factors such as resource competition and new threats from disease. Singapore has three native species of non-human primates: Sunda Slow Loris Nycticebus coucang, Long-tailed Macaque Macaca fascicularis, and Raffles’ Banded Langur Presbytis femoralis. Over the past few months, several non-native Dusky Langurs Trachypithecus obscurus were observed in Singapore. We document our observations, compile reports from social media, and attempt to assess the potential impacts on local primates. Whenever Dusky Langurs were encountered, we recorded the date, time, GPS coordinates, group demographics, and behaviour, including interactions with native primates. We also monitored sighting reports of Dusky Langurs posted on local major Facebook groups from 30 December 2019 to 31 January 2020, and privately messaged the person(s) for more information. On 31 August 2019, three Dusky Langurs were seen near a residential area in the northern part of Singapore, and two to three individuals were reported on 14 subsequent occasions. During one encounter on 18 January 2020, an adult male Long-tailed Macaque chased a group of Dusky Langurs from a feeding tree. The next day the same group of Dusky Langurs chased a group of 11 Banded Langurs from another feeding tree. The Dusky Langurs appeared to be healthy and wild, indicating that they may have swum across the Johor Strait and/or traveled on the Johor-Singapore Causeway from Malaysia. Further monitoring of these Dusky Langurs will be required to assess their impact on local primates.
The breeding season of fishes plays an important role in fish domestication and conservation of fish diversity. Freshwater goby, Glossogobius giuris is an important food fish of Bangladesh. Therefore, a study was performed to determine the breeding biology through assessing the gonadosomatic index (IG), fecundity and histology of gonad of G. giuris. A total of 1371 females and 1051 male fishes were collected from the Belai beel of Gazipur district. Significantly (P<0.05) higher values of mean IG were observed during March and from June to August for both females and males. The highest mean fecundity was recorded in August and the lowest was recorded in May. The smallest mean oocyte length was 0.037±0.005 mm in May and the largest was 0.071±0.001 mm in August. The early and late perinucleolar stages of oocytes were observed from January to March. The yolk vesicle stage was observed during April to May and yolk granule stage was observed during March and from June to August. These results revealed that G. giuris might breed in March and from June to August. Ann. Bangladesh Agric. (2019) 23(1) : 1-13
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.