The leaf litter is first sifted and then placed in the top section of a closed hanging bag. A similar appraoch for processing leaf litter in the field where the heat source is the sun is to use a Winkler Sifter. It will also allow more litter to be sampled when using a limited number of funnels. This will concentrate the litter and remove larger leaves and twigs. A method to improve the catch when using a funnel is to sift the leaf litter through a coarse screen before placing it above the funnel. This method works especially well in rain forests and wet sclerophyll areas. As the leaf litter dries from above, ants (and other animals) move downward and eventually fall out the bottom and are collected in alcohol placed below the funnel. This is most commonly done by placing leaf litter on a screen above a large funnel, often with a heat source above the leaf litter (a Berlese funnel). One of the most successful ways to locate these small, cryptic foragers is to collect the leaf litter in which they are foraging and extract the ants from it. Hand collecting these species can be difficult. Many ants are small and forage primarily in the layer of leaves and other debris on the ground. It is also impossible to associate different castes with conspecifics that may be present in the same sample or to know if individuals of one species came from the same colony or many. Also, they do not capture certain details and information about the species, e.g., a pitfall trap does not reveal where its captured ants were nesting. The disadvantages of these methods include the time needed to sort ants from other stuff, typically other insects and debri, then to further separate ants into distinctive species/forms. Standardized samples can make it possible to compare sets of samples with others. They can be used for ecological research aimed at quantifying diversity, i.e., to produce a species list or to quantify the relative abundance of ants occurring in the sampled area. They allow for sampling that targets specific environments, habitats, or areas within a habitat. The advantages of these methods are many. For each sample there can be a collection of different species and castes of ants, along with insects bycatch. Many of these methods will yield indiscriminate samples of ants. 2.5 Special Microhabitat Collection Methods.2.4 Artificial Nests and Subterranean Probes.2.3 Breaking Twigs and Chopping into Coarse Woody Debris.2 Collection Methods that find ant nests and retrieve nest series.1.12 Malaise Traps and yellow pan traps.For a general overview of collecting methods, see Upton (1991). These include hand collecting, using baits as attractants, ground litter sampling, and the use of pitfall traps. To collect as wide a range of species as possible, several methods should be used. Unfortunately, these methods are not always compatible, with the taxonomist sometimes overlooking species in favour of those groups currently under study and while the ecologist often collects only a limited number of specimens of each species, thus reducing their value for taxonomic investigations. For ecological studies, the most important factor is collecting identifiable samples of as many of the different species present as possible. For taxonomic studies, long series from a single nest which contain all castes (workers, including majors and minors, and if present, queens and males) is desirable to allow the determination of variation within species. The methods used will depend on the final purpose of the collections. Collecting can be as simple as picking up stray ants and placing them in a glass jar or as complicated as completing an exhaustive survey of all species present in an area and estimating their relative abundances.
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