A simple method for collecting specimens from foliage by beating or shaking them into a tray, sheet, bag or upturned open umbrella.
Vigorous use of a sweep net through, for example, grasses is also effective. The net’s contents are emptied into a tray for examination.
Motorised suction samplers are a good method for obtaining live specimens, collecting large numbers of individuals and species (Arnold 1994).
A number of portable models are available, e.g., the D-Vac (Dietrick & Schlinger 1960) and Uni-Vac (Arnold et al. 1973).
Uni-Vac The Uni-Vac incorporates a long flexible suction tube leading into a specimen chamber. It can be adapted for Acari by fixing a convenient length of plastic drainpipe into the suction tube and a close weave cotton bag or cloth (e.g., a handkerchief) over the free end of the pipe. Specimens pass directly into the bag instead of being exposed to damage during the long journey through the suction tube.
Handheld vacuum cleaner A domestic handheld vacuum cleaner is an inexpensive alternative to a purpose-built sampler. First make sure the dust container is empty, then move the cleaner backwards and forwards a few times through the vegetation to be sampled. Turn out the container into a shallow tray to see the results.
Chiggers (ectoparasitic larval Trombiculidae) will congregate within about 15 minutes on almost any foreign object dropped onto the ground. They respond positively to light and so will move out from under the shadow of the object.
A simple trap comprises a 0.5 m square of lightproof material with a 5 cm window of, for example, cellophane incorporated into the middle of it (Jones 1950, Steffey & Wingo 1975). The trap is laid over the investigation area and the edges weighted down.
Any chiggers present will move towards the window and collecting on the lower surface of the trap.
Carbon dioxide can be used to attract host-seeking ticks of some species by putting a1 kg block of dry ice (solid carbon dioxide) into a perforated container at the centre of a white sheet (Olkowski et al. 1990).
Modifications include
A drag is a flannel sheet or blanket (approximately 1m x 1.5 m) with a pole sewn into one edge. A length of rope is attached to either end of the pole. The drag is slowly pulled over the ground by the rope. Ticks that attach to the sheet, mistaking it for a passing host, are regularly removed using forceps or fingers. Some collectors sew a chain or line of heavy metal washers along the edge parallel to the pole in order to maximize contact with the ground.
Flagging is similar to dragging but the flag is swept from side to side in front of the operator and is more suitable for collecting from taller vegetation. A flag is a square of sheet or blanket pulled by one corner. Attaching a batten that is slightly longer than the edges provides a handle. Efficiency is improved by using a number of parallel strips of cloth with a chain link fixed to each free end (Gray & Lohan 1982). A flag fitted with a long, jointed handle has the advantage of allowing the user to remain upright while flagging in dense vegetation and under fallen branches (Carroll & Schmidtmann 1992).