Methods

Naturalis expedition, Vietnam, September-October 2009

Spiders were sampled from three localities in northern Vietnam: Cat Ba, Cuc Phuong, and Vu Quang. We established a one-hectare square plot in a protected forest habitat at each location and conducted a structured inventory (Coddington et al. 2009, Coddington et al. 1991, Scharff et al. 2003, Sørensen et al. 2002). Five methods were employed for collecting spiders: 1) beating vegetation during the day (BED), 2) searching for spiders in the aerial stratum at night (LUN), 3) searching for spiders on the ground during the day (LDD), 4) searching for spiders on the ground at night (LDN), 5) extraction of sifted leaf litter using a Winkler trap (WIN; Fachgeschäft & Buchhandlung für Entomologie, Vienna, Austria, www.entowinkler.at). Searching and beating methods were conducted in one-hour blocks; leaf litter sifting was done in two hour blocks plus a minimum hanging time of 48 hours.

Sites
Cat Ba
Hai Phong Province: Cat Ba National Park, Tuyen Duung Giao Duc Moi Truung - Du Lich Sinh Thai [Forest Education Trail], 20.797179°N, 107.006982°E, 50 m, 18 October-23 October 2009. Jeremy MILLER, PHAM Dinh Sac, HIEU Dao Ngoc
Samples:
BED: 6; LUN: 12; LDD: 4; LDN: 8; WIN: 5
TOTAL: 35

Cuc Phuong
Ninh Binh Province: Cuc Phuong National Park, Cay Dang Co Thu trail, 20.299039°N, 105.655756°E, 200 m, 7 October 2009-13 October 2009. Jeremy MILLER, PHAM Dinh Sac, Eulàlia GASSÓ MIRACLE
Samples:
BED: 4; LUN: 10; LDD: 4; LDN: 6; WIN: 4
TOTAL: 28

Establishing a 1 hectare plot at Cuc Phuong National Park

Vu Quang
Ha Tinh Province: Vu Quang National Park, forest near Don Bien Phong [border station] 567, 18.331306°N, 105.439111°E, 50 m, 27 September 2009-4 October, 2009. Jeremy MILLER, PHAM Dinh Sac, Eulàlia GASSÓ MIRACLE
Samples:
BED: 5; LUN: 9; LDD: 6; LDN: 6; WIN: 4
TOTAL: 30

Collecting methods
BED: beating vegetation during the day, one hour per sample
LUN: searching for spiders in the aerial stratum at night, one hour per sample
LDD: searching for spiders on the ground during the day, one hour per sample
LDN: searching for spiders on the ground at night, one hour per sample
Miller performing a LDN
WIN: extraction of sifted leaf litter using a Winkler trap, two hours leaf litter sifting plus a minimum hanging time of 48 hours per sample
Pham Dinh Sac sifting leaf litter Miller and Pham loading concentrated leaf litter into Winkler trap Winkler traps drying concentrated leaf litter

Literature Cited
Coddington, J.A., I. Agnarsson, J.A. Miller, M. Kuntner & G. Hormiga (2009) Undersampling bias: the null hypothesis for singleton species in tropical arthropod surveys. Journal of Animal Ecology 78: 573-584. Link to Publication
Coddington J.A., C.E. Griswold, D. Silva Dávila, E. Peñaranda & S.F. Larcher (1991) Designing and testing sampling protocols to estimate biodiversity in tropical ecosystems. In: E.C. Dudley (ed.), The Unity of Evolutionary Biology: Proceedings of the Fourth International Congress of Systematic and Evolutionary Biology, pp. 44-60, Dioscorides Press, Portland, OR. Link to Publication
Scharff, N., J.A. Coddington, C.E. Griswold, G. Hormiga & P.d.P. Bjørn (2003) When to Quit? Estimating species richness in a northern European deciduous forest. Journal of Arachnology 31: 246-273.Link to Publication
Sørensen, L.L., J.A. Coddington & N. Scharff (2002) Inventorying and estimating subcanopy spider diversity using semiquantitative sampling methods in an afromontane forest. Pest Management and Sampling 31: 319-330.Link to PDF