AUTUMN 1989 SHORT COMMUNICATIONS 117

MENDELSOHN,J. 1988. Communalroosting and feeding 4554 Shetland Green Road, Alexandria, VA 22312. Ad- conditions in Blackshouldered Kites. Ostrich 59:73-75. dress of second author: 2188 Hackberry Circle, WAIAN, L. B. AND R. C. STENDALL. 1970. The White- Longmont, CO 80501. tailed Kite in California, with observationson the San- ta Barbara population. Cal. Fish Game 56:188-198. Received16 September1988; accepted30 June 1989

J. Raptor Res. 23(3):117-120 ¸ 1989 The Raptor ResearchFoundation, Inc.

THE BARTOS TRAP: A NEW RAPTOR TRAP

ROBERTBARTOS, PENNY OLSEN AND JERRY OLSEN

Many effectivemeans of live trappingbirds of prey are and hunting hawks. World Press, Colorado), Swedish available, including bal-chatri [Berger, D. D. and H. C. Goshawk trap (e.g., Beebe and Webster 1964) and its Mueller. 1959. The Bal-Chatri: A trap for birds of prey. derivatives,and "flip trap" [e.g., Cam-Hardy universal BzrdBandinœ30:18-26; Olsen, J. and P. Woollard. 1975. raptor trap, Cam. G. R. 1985. A universalraptor trap. The use of the bal-chatri in banding. CanberraBird Notes Cotella 9(2):55-58]. The most appropriate trap will de- 3(4):8-9], noosecarpet, mist net and dho-gazza(e.g., Beebe, pend upon target speciesand circumstances.Sometimes FL. and H. M. Webster. 1964. North Americanfalconry settinga variety of traps is useful to increasethe chances

Figure 1. Assemblyinstructions for the Bartos Trap. 1 18 SHORT COMMUNICATIONS VOL. 23, No. 3

Figure 2. Assernblyinstructions for trigger mechanism. of capturing a particular raptor, or, when recapture is Trap Construction. The main ring (Fig. la), bow arm necessary,to overcomethe problemof avoidanceof a type (Fig. lb), and divider frame (Fig. l c) are made from of trap in which the raptor has already been captured. solderedmetal rod approximately 4 mm dia. Remaining Here we report on a versatile and convenientnew trap, sectionsof the frame are heavygauge wire (approximately designedby RobertBartos, which has several unique char- 10-12 gauge). An inexpensivefishing scoopnet (black acteristics.The Bartos Trap can be suspendedat almost tetron or similar) forms separatenetting compartmentsfor any height(e.g., in a buildingor in a tree near a nest),to raptor and lure. The net's diameter at full stretchdeter- capture speciesreluctant to ventureto the ground.Once minesthe sizeof the elliptical main ring (in our trap about capturedthe raptor is enclosed:unlikely to injure itself 62 cm x 57 cm) and bow arm. In our trap the divider is and safe from predators.The trap need not be attended about 33 cm dia, the spreaderarms (Fig. ld) 21 cm long, and thus has severaladvantages over a mist net type of and the length of the swing for the lure compartment12 trap. When assembledin alternativeform and seton the cm (Fig. le) and lure perch (Fig. If) 21 cm. The baseof ground,the trap is similar to the "flip trap" (seeabove). the lure compartment (Fig. l h) is simply a wire kitchen Further, the trap can be collapsedflat for easycarrying. strainer, in our case21 cm in diameter. Springs for the Sofar we haveused the trap to captureonly 2 particular bow net (Fig. l g) are modified springsfrom a rat trap. individual raptors:a CollaredSparrowhawk (Accipiter cir- We coveredthe bow ring and adjoining half of the mmn rhocephalus)unable to escapefrom a warehouseand a ring with refrigerationtubing to lessenthe chanceof injury Boobook Owl (Ninox novaeseelarzdiae)in a wooded pad- to the raptor by the closingbow. dock, recaptured for removal of a radio transmitter. In The trap is assembledas shown(Fig. 1). Wire mesh•s both casesthe trap was left and the raptor capturedon tied to the divider ring to form the base of the top com- our return about 2 hr later. We have also caught Kook- partment and protect the lure. Spreader arms (Fig. l d) aburras (Dacelogigas) and Pied Currawongs(Streperagra- are attachedto the divider sothat they can be folded;arms culina), and, with a sparrow as a lure and the trigger set clip onto the main ring and can be removedfor folding fine, House Sparrows(Passer domesticus). The swing (Fig. le) can alsobe clippedon or left of[. The AUTUMN 1989 SHORT COMMUNICATIONS 119

c

/ //

Figure 3. Various trap settings:a. folded for transport; b. set angled on the ground; c. set flat on the ground; d. set hanging. 120 SHORT COMMUNICATIONS VOL. 23, NO. 3

strainer must have bayonet slits cut into it (Fig. l h) and can be clipped either to the frame, beneath the trigger, or to the swing. Once the wire frame is set together, netting can be stretchedover and securedwith string around the main ring, bow net (so that the netting is taught when the bow is closed)and divider. The rest of the netting hangsdown and can be secured,as required, dependingupon the way the trap is used. The trigger device (Fig. 2, shown in cross section) is screwedto the divider frame over the top of the wire. The trigger setting fingers (Fig. 2a) are made from the setting rod of a mousetrap, or similar material (about 2 cm long on our trap). The trigger string (Fig. 2b) can be set low on the fingersto catchsmall birds (e.g., sparrows)or higher (for maximum tension) to catch large raptors. We made the trigger "perch" (Fig. 2c) from wood. Use of Trap. A lure is placedin the lower compartment: either a mouseor small passefineif set on the ground, or bird if set hanging. In an attempt to capture the lure a raptor entersthe trap through the top and percheson or trips the trigger device(Fig. 2d). The bow net then quickly flips closed.The bird is securedin a strong netting com- partment that is nonabrasive,unlike the wire netting used on someother typesof trap, and is unlikely to damagethe cere or break flight feathers. The trap is collapsedflat for easytransport (Fig. 3) and can be assembledin 2 ways: 1) with the lure compartment clippeddirectly beneath the dividerfor useon the ground, and set either angledtoward the target bird (Fig. 3b) or flat (Fig. 3%4a); or 2) with the lure compartmenthanging beneath the divider and the netting stretchedmore fully andset suspended (Fig. 3d, 4b). RobertBartos will provide further detailsand acceptorders for the trap from licensed trappers.

Lot 5 Lamont Close, Mardi, N.S.W. 2259, AUSTRA- LIA. Address of second author: P.O. Box 84 Lyneham, A.C.T. 2602, AUSTRALIA. Address of third author: R.M.B. 1705 Read Rd., Sutton, N.S.W. 2620, AUSTRALIA.

Received 8 December 1988; accepted30 June 1989

Figure 4. The BartosTrap: A. seton the ground;B. set hanging from a tree.