Jerry P. Clark Primary Staff Biologist California Department of Food CROWNED and Agriculture Sacramento, California 95814 SPARROWS Scott E. Hygnstrom Extension Wildlife Damage Specialist Department of Forestry, Fisheries and Wildlife University of Nebraska Lincoln, Nebraska 68583-0819

Fig. 1. White-crowned sparrow, Zonotrichia leucophrys (left) and golden-crowned sparrow, Zonotrichia atricapilla (right)

Damage Prevention and Repellents Identification Control Methods Capsicum White-crowned sparrows (Zonotrichia Toxicants Exclusion leucophrys, Fig. 1) are distinguished by None are registered or currently their pink or yellowish bill, erect Protect small areas with screened or available for use. posture, gray throat and breast, and netted frames prominent crown streaked with black Trapping Habitat Modification and white. Geographic races, including Lily pad, cloverleaf, or modified the mountain (Z. l. oriantha), Gambel’s Remove unnecessary cover around Australian crow traps. (Z. l. gambelii), Nuttall’s (Z. L. nuttalli), valuable crops. and Puget Sound white-crowned Frightening sparrow (Z. l. pugetensis) show minor differences in head pattern, bill color, Use propane exploders in conjunction and song. Their songs vary geographi- with shotgun fire, shell crackers, cally, but consist primarily of clear bombs or whistles, and raptor- whistles. mimicking kites. Avitrol®.

PREVENTION AND CONTROL OF WILDLIFE DAMAGE — 1994 Cooperative Extension Division Institute of Agriculture and Natural Resources University of Nebraska - Lincoln United States Department of Agriculture and Plant Health Inspection Service Animal Damage Control E-97 Great Plains Agricultural Council Wildlife Committee Golden-crowned sparrows (Zonotrichia taken during the breeding season. deciduous fruit trees. Occasionally, a atricapilla, Fig. 1) are similar in During the winter months white- few trees near a wood or brush pile appearance to white-crowned spar- crowned sparrows feed primarily on may be severely attacked. Depreda- rows with the exception that they have seeds. The diet of golden-crowned tions increase as the buds swell. no white head stripes. Instead, adults sparrows is thought to be similar. have a dull golden-yellow central Legal Status crown stripe that is heavily bordered General Biology with black. Immatures look like female Crowned sparrows are classified as house sparrows, but are larger, darker, Gambel’s white-crowned sparrows migratory nongame in the Code have longer tails, and usually have a appear in California valleys in Septem- of Federal Regulations. Depredation yellowish crown. Their song consists ber and reach their maximum density permits are required from the US Fish of three to five clear whistles that during October, becoming injurious to and Wildlife Service before any control descend in scale. They are less numer- crops in localized areas. They remain activities can be initiated. Crowned ous and cause fewer problems than extremely abundant until March and sparrows may be controlled in Cali- white-crowned sparrows. gradually leave by May. fornia under the general supervision of the county agricultural commissioner. Nests are built in bushes or on the Range ground among mosses sheltered by higher vegetation. White-crowned and Damage Prevention and White-crowned sparrows are abun- golden-crowned sparrows lay 3 to 5 Control Methods dant in the western United States. eggs. One brood is raised per year. They breed primarily in Alaska and Incubation takes 12 days, with age at Exclusion Canada and winter in the western and first flight commonly 10 days. southern United States and Mexico. To protect flower seedlings and home Breeding and wintering ranges overlap vegetable gardens, grow plants under in California, Oregon, Washington, Damage and Damage frames covered with wire or plastic and other western states. Gambel’s, Identification netting. the most important, race, breeds in Alaska and western Canada but win- The crowned sparrows are involved in Habitat Modification crop depredations over a wide area ters in the interior valleys of California Since crowned sparrows usually feed and upon a great variety of crops. and from San Francisco Bay south- within a few yards of secure cover, the Newly sown lawn grass and garden ward. elimination of all useless brush piles, and flower seedlings are often com- rolls of wire, and stacks of wood Golden-crowned sparrows breed pletely consumed. Waves of migrating around vulnerable crops is desirable. along the coast from Alaska to north- crowned sparrows have been known Eliminate weedy borders along fields. ern Washington and winter west of the to destroy every small flower and Destroy fence rows and unnecessary Cascades and in the Sierra Nevada to vegetable plantlet in home gardens. shrubbery if occupied by sparrows. Baja California. They migrate south to The damage is most severe in areas California in October and stay until adjacent to brushy river bottoms. Ex- Frightening April. tensive damage often occurs to com- mercial plantings of lettuce, broccoli, Historically, the most widely used Habitat sugar beets, alfalfa, and grain. Depre- sound devices for minimizing dations are most noticeable in field crowned sparrow depredations have White-crowned sparrows are birds of crops that are adjacent to river bottom been the automatic propane exploders. the chaparral, brushy river bottoms, brush or weedy fields or have shrub- These units should be moved every brush piles, rubbish heaps, dense weed bery or trees planted for windbreaks. day or two to prevent the birds from fields, and fence rows. They common- Damage occurs along the margins of becoming habituated to the sound. ly winter in dense hedges and thick the fields near dense cover favored by Shell crackers fired from a 12-gauge plantings of shrubbery found near these birds and is usually limited to shotgun, bird bombs, and whistlers towns and suburbs. Golden-crowned the outer 50 to 100 feet (15 to 30 m) of discharged from a 6-mm flare pistol sparrows commonly winter in boreal the field. Seedlings are often consumed are commonly used to frighten spar- scrub and spruce. by crowned sparrows when crop rows from damaged fields. Some seeds germinate and emerge from the growers have reported limited success soil. Damage normally stops when the with raptor-mimicking kites tethered Food Habits seedlings reach a height of 3 or 4 to stationary posts positioned along inches (7.6 to 10.2 cm). crop borders. Food of white-crowned sparrows averages 75% plant and 25% animal Crowned sparrows play a minor role Avitrol® Mixed Grains (0.5%) is a toxic matter. Most of the animal food is in debudding almond and other chemical that produces flock-alarming

E-98 reactions in birds that ingest a sufficient Trapping Trapped crowned sparrows serve as quantity. It is currently registered in decoys to other birds. Decoy birds are Crowned sparrows are usually quite California to control crowned sparrows usually essential in attracting other easy to trap using lily pad or clover- that may damage sprouting crops. crowned sparrows. Use one to five live leaf traps and have been taken by Prebaiting is usually necessary with decoys, depending on the size of the modified Australian crow traps. Use untreated grain (fine chick scratch) to trap. Provide food and water at all milo or finely cracked corn as bait. establish a feeding pattern. The prebait times to keep decoys alive and to make should be placed in trays in the same The lily pad trap and cloverleaf trap the trap more attractive to wild birds. area where the treated bait will be ex- are easy to set up and peg to the Canary grass seed, wild bird seed mix, posed. Avitrol®-treated chick scratch ground (Fig. 2). They are effective in or chick scratch work well to maintain must be exposed in trays only. Set trays catching small numbers of crowned decoy birds. Install 1/4-inch (0.6-cm) out in the field after the crop is planted sparrows. These traps are usually 3 dowel rods to serve as perches, espe- and before crowned sparrows have feet (1 m) high and 3 feet (1 m) wide. cially in larger traps. Perches should moved into the area. Each bait tray run the full length of the trap, about 1 Australian crow traps are used to cap- should contain one part Avitrol® Mixed foot (30 cm) from the sides and half- ture crows, magpies, and ravens. The Grain concentrate with two to nine way between the top and the bottom traps can be modified by changing the parts of untreated fine chick scratch. of the trap. Cold winds or hot sun can entrance, and used to capture The quantity of treated bait to expose stress trapped birds. Fasten burlap to crowned sparrows, starlings, black- per tray will vary depending on the the sunny side of the trap to provide birds, house finches, and house spar- amount taken by crowned sparrows shade in the summer. rows (Fig. 3). Minor modifications can during prebaiting. Several trays should be made to fit the trap on a truck or With small traps, the captured birds be placed where the birds are normally trailer. The basic design of the trap, may be removed by hand. Birds can be observed. Bait should be replaced if it however, should not be changed. removed from modified Australian becomes water soaked or depleted. crow traps by hand or with a small Proper trap location is one of the most net. Several birds can be removed by Repellents important factors in achieving good cutting a 6 x 6-inch (15 x 15-cm) exit results. Observe the problem area to Granular formulations of capsicum are hole that is easily opened and closed in determine flyways and resting, perch- federally registered for repelling spar- an upper corner of the rear of the trap. ing, and feeding areas before placing rows from certain fruit, vegetable, and Place a small holding cage on the out- traps. Place traps in open areas where grain crops. Read the product label for side of the trap over the open exit hole they can be easily seen. Traps have specific information. and herd the birds from the trap into been most effective where birds enter the holding cage. To euthanize the fields and orchards, or near resting Toxicants birds, place the holding cage in a plas- and perching sites. None are registered. tic bag and inject carbon dioxide through a hose until the birds are dead. Burn or bury the dead birds.

2 - 3'

2 - 3' 3'

3'

Fig. 2. Lily pad and cloverleaf traps.

E-99 16" 8' Slot: 1 3/4" wide 6' 1' 4" 4" Drop block: 1"x1" x 6' long 16"

Entrance — end view Entrance

Assembled Trap

a Important Assembly Instructions: Place end panels between side panels; otherwise, top panels will not fit properly. Note: a. Reinforce this area with a 2 x 4 x 16-inch (5 x 10.2 x 40.6- cm) b piece of wood. This provides a greater surface area for the entrance to rest on. b. Place a small door in this area for removal of trapped birds.

Materials Needed For Trap: 15 boards - 1 x 4s, 8 feet long (2.5 x 10.2 cm, 2.4 m long) 25 boards - 1 x 4s, 6 feet long (2.5 x 10.2 cm, 1.8 m long) 4 boards - 1 x 1s, 8 feet long (2.5 x 2.5 cm, 2.4 m long) 1/2-inch exterior plywood - 16 inches x 8 feet (40.1 cm x 2.4 m) 1/2-inch mesh aviary wire - 3 x 80 feet (0.9 x 24.4 m) 2 hinges staples Fig. 3. Modified Australian crow trap.

Acknowledgments For Additional Information Figures 1, 4, and 5 from Clark (1986). Figures 2 and 3 were adapted from Robbins et Beal, F. E. L. 1910. Birds of California in relation al. (1983) by David Thornhill, University of to the fruit industry. Biol. Survey Bull. No. Nebraska-Lincoln. 34. US Dep. Agric. Clark, J. P. 1986. Depredating birds. Pages 701-1 - 726-1 in J. P. Clark, ed. Vertebrate pest control handbook. Calif. Dep. Food Agric. Sacramento. Peterson, R. T. 1961. A field guide to western birds. Houghton Mifflin Co. Boston. 309 pp. Robbins, C. S., B. Brunn, and H. S. Zim. 1983. Birds of North America. Golden Press. New York. 360 pp.

Editors Scott E. Hygnstrom Robert M. Timm Gary E. Larson

E-100