Insect (Hymenoptera) Biodiversity Across Forest Canopy and Understorey in SE-Asia BIFA5_026

Study Extent

The study was conducted in the tropical forests of Mo Singto area at Khao Yai National Park (14N, 101E) and Klong Naka Wildlife Sanctuary (9N, 99E). Sampling occurred in June and December 2019 at Khao Yai and in March and September 2020 at Klong Naka.

Sampling

At Mo Singto, we conducted insect sampling within the 30-ha monitoring plot designed to study vegetation and vertebrate (mainly gibbons) communities (Brockelman et al. 2011). Similarly, we used the 20-ha monitoring plot established in 2019 at Klong Naka designed to study vegetation community dynamics. These monitoring plots are subdivided into 20 m x 20 m subplots. Within each monitoring plot, we set a 300 x 300 m square area and established nine sampling points (3 x 3 grid arrangements). We used nine of the sub-plots where these nine sampling points were located. At each of the nine 20 m x 20 m sub-plots, we found suitable trees where traps can be suspended at the canopy and understory strata. Understory traps were suspended at 2 m above the ground, whereas canopy traps were suspended immediately below the canopy foliage. The height of the canopy traps changed depending on the tree height (the information on the height of the traps is provided in the sampling event data). We selected a tree whose top foliage received direct insolation, but we did not select midstory or emergent trees. The ropes to suspend the canopy traps were hung over the tree branches by first shooting the throw line (2 mm diameter, BARHAR, Dongguan, Guangdong, China) using an arborist slingshot (Big Shot Line Launcher, WesSpur Tree Equipment, Bellingham, WA, USA). The throw line was replaced with a nylon rope (approx. 8-10 mm diameters) to which the trap was attached and hoisted to the canopy stratum. A nylon rope was also used to suspend the traps at the understory. Yellow-pan flight interception traps (yellow-pan FITs) consisted of four 15 cm x 60 cm clear acrylic panes set at right angles and erected above the yellow polypropylene tub (34 cm diameter x 14 cm depth) and covered by 2 mm thick vinyl plastic sheet (55 cm diameter). For the traps suspended in the canopy, we added 1800 ml of ethylene glycol and 1200 ml of 95% ethanol in the tub, whereas we added 1200 ml of ethylene glycol and 800 ml of 95% ethanol in the understory tubs as the rate of evaporation was lower in the understory. At each sampling event, we run the traps for 10 consecutive days. The samples were then taken to a bottle, and the ethylene glycol was replaced with 99% ethanol. All hymenopteran specimens were taken, and representative specimens were dry-mounted for identification. We used Goulet and Huber (1993) to identify the specimens to family and then morphospecies with assistance from Dr Alexey Reshchikov. All wet and dry specimens were stored at the Mahidol University Museum of Natural History. Brockelman, W. Y., Nathalang, A. and Gale, G. A. 2011. The Mo Singto forest dynamic plot, Khao Yai National Park, Thailand. Natural History Bulletin of the Siam Society. 57: 35-55. Goulet, H. and Huber, J. T. 1993. Hymenoptera of the world: An identification guide to families. Centre for Land and Biological Resources Research, Ottawa, Ontario, Canada.

Quality Control

The field surveys were mainly conducted by the local assistants and students, but supervisors visited both Mo Singto and Klong Naka to check the sampling areas and ensure that the fieldwork followed the sampling protocols described above. Taxonomic identification has been conducted by the students and they collaborated with local taxonomists to check their family-level identification.

Method steps

1. 1. At each of the nine 20 m x 20 m sub-plots, we found suitable trees where traps can be suspended at the canopy and understory strata. Understory traps were suspended at 2 m above the ground, whereas canopy traps were suspended immediately below the canopy foliage. The height of the canopy traps changed depending on the tree height (the information on the height of the traps is provided in the sampling event data). 2. We selected a tree whose top foliage received direct insolation, but we did not select midstory or emergent trees. The ropes to suspend the canopy traps were hung over the tree branches by first shooting the throw line (2 mm diameter, BARHAR, Dongguan, Guangdong, China) using an arborist slingshot (Big Shot Line Launcher, WesSpur Tree Equipment, Bellingham, WA, USA). The throw line was replaced with a nylon rope (approx. 8-10 mm diameters) to which the trap was attached and hoisted to the canopy stratum. A nylon rope was also used to suspend the traps at the understory. 3. Yellow-pan flight interception traps (yellow-pan FITs) consisted of four 15 cm x 60 cm clear acrylic panes set at right angles and erected above the yellow polypropylene tub (34 cm diameter x 14 cm depth) and covered by 2 mm thick vinyl plastic sheet (55 cm diameter). For the traps suspended in the canopy, we added 1800 ml of ethylene glycol and 1200 ml of 95% ethanol in the tub, whereas we added 1200 ml of ethylene glycol and 800 ml of 95% ethanol in the understory tubs as the rate of evaporation was lower in the understory. 4. At each sampling event, we run the traps for 10 consecutive days. The samples were then taken to a bottle, and the ethylene glycol was replaced with 99% ethanol. 5. All hymenopteran specimens were taken, and representative specimens were dry-mounted for identification. We used Goulet and Huber (1993) to identify the specimens to family and then morphospecies with assistance from Dr Alexey Reshchikov. All wet and dry specimens were stored at the Mahidol University Museum of Natural History.

N/A

1. Hymenoptera
   rank: order
2. Arthropoda
   rank: phylum
3. Insecta
   rank: class
4. Torymidae
   rank: family
5. Vespidae
   rank: family
6. Trichogrammatidae
   rank: family
7. Animalia
   rank: kingdom

MoSingto area at Khao Yai National Park (14N, 101E) and Klong Naka Wildlife Sanctuary (9N, 99E). In each location, a total of nine sampling points (300 x 300 m grid) were set within the forest dynamic plots (ForestGEO plots).