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Research

Golf Courses Help SaveBurrowing OwlsGolf courses can play a positive role in theconservation of this threatened species.BY MATTHEW D. SMITH AND COURTNEY J. CONWAY

urrowing owls are intriguingbirds because, unlike mostowls, they are readily visible

during daylight hours and aretolerant of human presence. Theirconspicuousness and peculiar nest-ing habits have made burrowingowls a popular bird in the westernUnited States. Yet, burrowing owlshave suffered population declinesin many portions of their NorthAmerican range.12 They are cur-rently listed as an endangered speciesin Canada and a species of nationalconservation concern in theUnited States.34

Burrowing owls lay their eggsin underground burrows that have

, Artificial burrows on golf courses had the same percent ofbeen abandoned by mammals such , . , , ,successful nesting attempts as the other three burrow types.as prairie dogs (Cynomys ludovidanus However, nests on golf courses produced fewer offspring perand Cynomys leucurus) and American nesting attempt than nests off golf courses,badgers (Taxidea taxus).3 A shortageof suitable burrows due to a declinein these mammals is thought to be onefactor contributing to declines in bur-rowing owl populations.6 To compen-sate for the shortage of natural burrows,managers and researchers often useartificial burrows to provide nestingsites for burrowing owls.7

GOLF COURSESPROVIDE HABITATBurrowing owls typically nest andforage in short-grass open areas andavoid areas with a high density of trees,shrubs, or tall grass.5 The characteristiclarge, open areas of manicured shortgrass on golf courses attract burrowing

owls. Indeed, burrowing owls often areseen foraging and nesting on golfcourses.8 However, burrowing owlsgenerally like to forage close to theirnest burrow, and golf courses often lacksuitable burrows required by owls. Golfcourses may be able to aid burrowingowl conservation by providing artificialnesting burrows. Because burrowingowls are still present in many areasthroughout the western U.S.,1 effectiveconservation efforts should be imple-mented immediately to reverse declin-ing population trends.

We examined the efficacy ofinstalling artificial nesting burrows ongolf courses as a way to help restore

local burrowing owl populations.9-10

We examined whether burrowingowls would locate and occupyartificial burrows installed on eightgolf courses in south-centralWashington (near the cities ofPasco, Kennewick, Richland, andMoses Lake) . We also wanted toknow which golf course features(such as proximity to fairways orsprinklers) influenced theprobability that owls would use anartificial burrow. We compared thereproductive success and annualfidelity (tendency to return to thesame nesting site) of owls nestingin artificial burrows on golf coursesto those nesting in natural andartificial burrows off golf courses,as well as natural burrows on golfcourses.9

OCCUPANCY ANDREPRODUCTIVE SUCCESSWe repeatedly visited each of our 405study burrows (130 artificial burrowson golf courses, 86 artificial burrows offgolf courses, 14 natural burrows on golfcourses, and 86 natural burrows off golfcourses) every 2-4 days throughout thebreeding season (February 1 throughAugust 31) in 2001 and 2002. Duringthese nest visits, we recorded thenumber of adult and juvenile owlsvisible, or any signs of occupancy suchas feathers, pellets, or feces.

We found many burrowing owls innatural burrows off golf courses. In2001, 56 burrows were used as nests, 14

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Table INumber of burrows used by burrowing owls in south-central Washington, 2001-2002.

Each year, we recorded whether burrows were: I) used as nests,2) occupied by anunpaired male, 3) used temporarily by owls (i.e., we rarely observed owls but found

signs of use such as pellets or feathers), or 4) not used by owls.

NestsOccupied by

Unpaired MalesUsed

Temporarily

2001 2002 2001 2002 2001 2002

Natural off golf course 56 72 14 17 40

Natural o n golf course 7 9 2 0 2

Artificial o f f golf course 6 5 1 0 2 7

Artificial o n golf course 2 2 1 4 6

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were occupied by unpaired males, and50 burrows were used temporarily. In2002,72 burrows were used as nests, 17were occupied by unpaired males, and37 burrows were used temporarily.Though less frequently, owls did occupyand nest in the other three burrowtypes, including artificial burrows ongolf courses. Burrowing owls usedfewer artificial burrows on golf courses(6.5%) compared to artificial burrowsoff golf courses (18%). However, theyused 35% of artificial burrows that wereinstalled in non-maintained areas andwere within 200 meters of a naturalnest.9

Two years after installing artificialburrows, the number of nests on golfcourses increased by only one. How-ever, the total number of adults on golfcourses increased by 24% (from 21 to26 owls), and the percent of golf courseowls occupying artificial burrows in-creased slightly (from 24% to 31%).Artificial burrows on golf courses hadthe same percent of successful nestingattempts as the other three burrowtypes. In contrast, nests on golf coursesproduced fewer offspring (average of2.3) per nesting attempt than nests offgolf courses (average of 3.9).9

We placed artificial burrows at a varietyof locations on each of our participatinggolf courses. Burrowing owls used 8 ofthe 130 artificial burrows on golfcourses. Four of these eight occupied

burrows were used as nests, and fourwere used by unpaired males. Burrow-ing owls used only one artificial burrowin a maintained area; the other sevenwere in non-maintained areas. Owlspreferred artificial burrows that werefurther from maintained areas (thosewith frequent mowing, watering, andgolfer traffic), fairways, and sprinklers,and those that were closer to existingnatural bur rows (Table I).9

ANNUAL FIDELITYLeg bands were placed on owls on thestudy site and surveys were conductedin 2001 and 2002 to locate all returningowls. We banded 74 owls in 2000,300owls in 2001, and 280 owls in 2002.Our results suggest that owls nesting ongolf courses (including both artificialand natural burrows) were more likelyto return the next year (followingmigration) compared to owls nesting

off golf courses (55% and 33%,respectively).9

WHAT DO THESERESULTS MEAN?Owls did not use a great number of theartificial burrows on golf courses (8 of130), and they only occupied artificialburrows on two of our eight participat-ing golf courses. In fact, these twocourses already had owls nesting innatural burrows on their property priorto our study. Hence, large-scale effortsto install artificial burrows on golfcourses do not appear to be an efficientuse of resources. Installing artificialburrows only on golf courses with owlsnesting nearby holds some potentialand should be evaluated on a larger(i.e., regional) scale. Such efforts arewarranted as golf courses may providebenefits for owls.

Nesting attempts in artificial burrowson golf courses appeared to be moresuccessful compared to other burrowtypes. Indeed, nests in artificial burrowstend to have lower depredation thannatural borrows,11 and annual sitefidelity at golf course burrows wasslightly higher than at burrows off golfcourses. Conversely, golf course bur-rows fledged fewer young than burrowsoff golf courses, and we need to payclose attention to this to ensure thatgolf courses are not detrimental to owls(i.e., they have features that entice owlsto attempt nesting, but contain other

Table 2Mean (0) and standard error (SE) of distance (m) to landscape features

between burrowing owl nests (n = 4) and unoccupied burrows (n = 120) andbetween occupied (n = 8) and unoccupied (n = 120) artificial burrows on golf

courses in south-central Washington. Adapted from Smith et al. (2005).

Landscape FeatureUnoccupied

BurrowsNest

BurrowsOccupiedBurrows

0 ± S E 0 ± S E 0 ± S E

Distance to maintained area* 18 ± 3 48 ± 24

Distance to rough* 15 ± 2 57 ± 33

Distance to fairway* 35 ± 3 74 ± 34

Distance to sprinkler* 23 ± 2 60 ± 26

Distance to nearest natural burrow* 579 ±25 149 ± 68

34 ± 15

34 ± 18

47 ± 19

43 ± 14

180 ±43

*Differed between occupied and unoccupied burrows based on one-tailed Mann-Whitney U-tests (P < 0.05).

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features that cause poor success). Inconclusion, some golf courses canenhance existing nesting opportunitiesfor burrowing owls, and they subse-quently may help to reverse localdeclines of owl populations.

RECOMMENDATIONS TOENHANCE SUCCESS OFARTIFICIAL NESTINGBURROWS ON GOLFCOURSES* Evaluate each golf course individually.

Artificial nest installation should beconsidered only for courses thatpresently have burrowing owls nestingnearby and that have suitable areas fornesting (described below).« Install artificial burrows in appropriateareas. For golf courses with nesting owlswithin ~0.5km of non-maintainedareas, burrows should be placed in areasthat have suitable owl foraging habitat,are 43 yards away from any sprinklerhead, are 38 yards away from all main-tained areas, and have relatively lowgolfer traffic.* Provide native habitat. Providing areaswith native vegetation and unmanicuredareas near artificial nests will increaseforaging habitat and may help attractburrowing owls.» Maintain artificial borrows. Artificialburrows require periodic maintenancebecause the substrate around theentrance commonly erodes. Once thetunnel entrance protrudes from theground, young nestlings cannot retreatto the safety of the burrow. Burrowsshould also be cleared annually to pre-vent debris from plugging the entrance,which happens frequently to burrowson golf courses.^ Ensure that burrows are not destroyedwhen changing course layout. Also, considertiming of construction: owls appear tobe sensitive to large-scale constructionduring the nesting season (March toJuly) and may nest elsewhere if con-struction is occurring nearby duringthe breeding season.

Inform golfers about your project. Mostgolfers were excited at the prospect of

Eight golfcourses wereused insouth centralWashingtonto see if

burrowingowls woulduse artificialburrows fornesting andproducing

fledglings.

seeing owls during a round of golf.Golfers and course staff also shouldknow that burrowing owls may need afew years to either locate newly con-structed burrows or to increase inpopulation size to fill the new nest sites.

LITERATURE CITED1. Dechant,J. A., M. L. Sondreal, D. H.Johnson,L. D. Igl, C. M. Goldade, P. A. Rabie, and B. R.Euliss. 1999. Effects of management practices ongrassland birds: Burrowing Owl. NorthernPrairie Wildlife Research Center, Jamestown,North Dakota. 31 pp.

2.Wellicome,T. L, and G. L. Holroyd. 2001.Thesecond international burrowing owl symposium:background and context.Journal of RaptorResearch 35:269-273.

3. James, P. C., and R.H.M. Espie. 1997. Currentstatus of the burrowing owl in North America:an agency survey. Pages 3-5. In J. L. Lincer andK. Steenhof (eds.).The burrowing owl: itsbiology and management. Raptor ResearchReport No. 9. Raptor Research Foundation.

4. U.S. Fish and Wildlife Service. 2002. Birds ofConservation Concern. Office of MigratoryBird Management, Washington, D.C., USA.

5. Haug, E. A., B. A. Millsap, and M. S. Martell.1993. Burrowing Owl (Speotyto cunkularid). InA. Poole and F Gill (eds.).The Birds of NorthAmerica, No. 61. Academy of Natural Sciences,Philadelphia, and American Ornithologists'Union, Washington, D.C., USA. 20 pp.

6. Desmond, M. J., and J. E. Savidge. 1996.Factors influencing burrowing owl (Speotytocunicularia) nest densities and numbers in westernNebraska. American Midland Naturalist 136:143-148.

7. Collins,T. C., and R. E. Landry. 1977. Artificialnest burrows for burrowing owls. North AmericanBird Bander 2:151-154.

S.Thomsen, L. 1971. Behavior and ecology ofburrowing owls on the Oakland MunicipalAirport. Condor 73:177-192.

9. Smith, M. D., C. J. Conway, and L. A. Ellis.2005. Burrowing owl nesting productivity: acomparison between artificial and natural bur-rows on and off golf courses. Wildlife SocietyBulletin 33(2): in press.

10. Conway, C. J., M. D. Smith, and L. A. Ellis.2003. Burrowing owl conservation on golfcourses in North America. Final Report, U.S.Golf Association, Wildlife Links Program,Stillwater, Okla.

ll.Wellicome.T. L, G. L. Holroyd, K. Scalise,and E. R. Wiltse. 1997. The effects of predatorexclusion and food supplementation on burrow-ing owl population change in Saskatchewan.Pages 487-497. In]. R. Duncan, D. H.Johnson,andT. H. Nicholls (eds.). Proceedings of thesecond international symposium of the biologyand conservation of owls of the northernhemisphere. USDA Forest Service GeneralTechnical Report NC-190.

ACKNOWLEDGMENTS to the participatinggolf courses: Buckskin Golf Course, CanyonLakes Golf Course, Columbia Point GolfCourse, Horn Rapids Golf Course, MeadowSprings Golf and Country Club, MosesPointe Golf Course, Sun Willows GolfCourse, and West Richland MunicipalGolf Course.

MATTHEW D. SMITH, graduate student,School of Natural Resources, The Universityof Arizona, Tucson; and COURTNEY J.CONWAY, PH.D., USGS ArizonaCooperative Fish and Wildlife ResearchUnit, School of Natural Resources, TheUniversity of Arizona, Tucson.

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