sign in sign up
<<
Home , Diving petrel, Petrel, Procellaria, Sooty albatross

SHORT COMMUNICATIONS 1111

TheCondor96:1111-1113 Q The CooperOmithological Society 1994

DIVING DEPTHS OF WHITE-CHINNED ’

N. Hum British Antarctic Survey,Natural EnvironmentResearch Council, High Cross,Madingley Road, Cambridge,CB3 OET U.K.

Key words: White-chinned ; diving depth; Burger and Wilson (1988) Prince and Jones (1992) feeding behavior; aequinoctialis. and Prince et al. (1994) that is 10 cm lengths of clear PVC tubing of 1 mm internal diameter, heat-sealed at For many , the ability to submerge to capture one end, with soluble indicator powder introduced into prey is a key adaptation for their foraging behavior. the other end. The gauge was attached with adhesive Studies of diving in seabirds have typically featured tape to a metal leg band. Breeding burrows were checked species known to be virtually dependent on long, often twice daily and recaptured on subsequent visits deep, dives for their livelihood, e.g., (re- to feed their chick. Birds were caught using a box, of viewed in Croxall et al. 1993) alcids (reviewed in Bur- dimensions 20 cm x 20 cm (aperture) x 50 cm (length) ger 199 1), cormorants (Wilson and Wilson 1988, Crox- with a trapdoor at one end, inserted into the mouth of all et al. 199 1, Wanless et al. 199 1). As far as the size a burrow. (A trapdoor alone was readily circumvented of the birds has permitted, these studies have pro- by the .) Because White-chinned Petrels typically ceeded from collecting data on maximum depth ofdive make lengthy foraging trips, averaging 34 days (Hall via multiple maximum depths to continuous records 1987) gauge deployments ranged from l-12 days. To of diving depth against time and recently, in the larger minimize disturbance to a species known to be sen- penguins, with simultaneous collection of velocity and/ sitive (Hall 1987) only one gauge deployment was made or locational data (Kooyman et al. 1992, Ancel et al. per individual. 1992). Gauges were recovered from 11 birds and the length Although some members of the of the tube still covered with indicator powder was and of other families of the (e.g., Su- measured to the nearest 0.5 mm. Maximum depth at- lidae) have long been known as proficient divers (Ku- tained was calculated by the equation: roda 1954, Ashmole 1971, Brown et al. 1978) only anecdotal information on the depths they attain has been available until very recently. The use of light- weight capillary gauges (Burger and Wilson 1988) has where d,,,,, is maximum depth (m), L, is the initial created opportunities to obtain reliable quantitative length (mm) of undissolved indicator and Ld the length data on the maximum depth reached by a wide variety (mm) on recovery (Burger and Wilson 1988). of seabirds, particularly penguins and alcids (Burger 1991) but also Cape Gaune& Sula capensis(.&%I& RESULTS and Walter 1993). South Georaia Divina Petrels Pele- The durations of gauge deployment and depths at- canoidesgeorgick (Prince and Jones 1<92), and four tained by each bird are given in Table 1. There was no species of Diomedeidae (Prince et al. 1994). significant difference in mean maximum depth be- With the exception of the highly specialized Peleca- tween the sexes (t = 1.46, P = 0.28) nor in relation to noididae, the Procellaridae (petrels and ) the size of the bird (whether expressed as mass, or as are the best adapted of the Procellariiformes for diving. mass corrected for body size using bill or wing mea- Species in this family may dive as much as 20 m deep surements). However, the maximum depth recorded (Skim 1979). This paper reports the first systematic was positively related to gauge deployment duration quantitative data on diving depths for any species of (depth = 2.58~+ 0.624 duration, r2 = 0.47, P = 10.05), petrel. although this relationship was no longer significant if the deepest dive was excluded. METHODS Fieldwork was carried out at Bird Island, South Geor- DISCUSSION gia (54“OOS,’ 38”02W)’ between 7-28 March 1993, ap- The results indicate that White-chinned Petrels reach proximately half-way through the chick-rearing period. depths of 13 m. Such depths are not dissimilar to those Seventeen capillary gauges were attached to adult birds reported for Pu#inus shearwaters of 40-60°h the mass that had returned to feed their chicks. Most birds were of White-chinned Petrels. Thus Skira (1979) recorded sexed (by comparison of bill measurements between Short-tailed Shearwaters P. tenuirostrisreaching lO- the two partners, males being the larger (N. Huin, un- 12 m and possibly 20 m, Brown et al. (198 1) reported publ. data). The gauges were similar to those used by Sooty Shearwaters P. griseusattaining 10 m and Wood (1993) recorded Flesh-footed and Fluttering shearwa- ters P. carneipesand P. gavia reaching 5 m and 2-3 I Received 15 April 1994. Accepted 27 July 1994. m, respectively. 1112 SHORT COMMUNICATIONS

TABLE 1. Maximum diving depths and gauge de- chinned Petrels. The only study of the species’ diet, at ployment durations of White-chinned Petrels at South South Georgia in 1985/1986 (Croxall et al., in press), Georgia. showed that Antarctic Euphausia superba, lan- temfishes Myctophidae and oceanic (mainly the ommastrephid Martialia hyadesi) were the main prey. hdPbgr' Mass Maximum All these frequently occur in large swarms or shoalsat Bird SW (9) WYS) depth(m) or near the sea surface (Croxall et al., in press) and 088 1,170 1 2.8 would probably be very suitabletargets for pursuit and 089 F 1,080 5 5.4 capture on relatively short and shallow dives. 090 F 1,400 12 12.8 I thank P. A. Prince for encouraaementand advice 091 M 1,150 5 8.3 in this study, J. Cooper for help& the field, J. R. 092 M 1,200 2 3.3 Ashford and M. J. Whitehouse for their unpublished 096 M 1,300 7 3.0 observations, J. P. Croxall for help in preparing the 097 F 1,330 6 9.1 manuscript,J. Leland for typing it and two anonymous 098 1,330 8 4.9 reviewers for helpful comments. 099 1,400 10 7.2 100 1,380 3 4.9 LITERATURE CITED 103 F 1,230 5 6.6 ADAMS,N. J., AM) C. B. WALTER. 1993. Maximum diving depths of Cape Gannets. Condor 95:734- It is not easy to assessthe accuracyof the results in 736. the presentstudy. Burgerand Wilson (1988) found that ANCEL, A., G. L. KOO~MAN, P. J. PONGAN~S,J.-P. gaugessubjected to simulated plunge-diving overesti- GENDNER,J. LIGNON,X. MESTRE,N. Hum, P. H. mated denths bv 39% and 9W on submeraenceto 5 m THORSON,P. ROBISSON,AND Y. LE MAHO. 1992. and 10 m, respectively. However, most observations Foraging behaviour of Emperor Penguinsas a re- on feeding by White-chinned Petrels indicate that they sourcedetector in winter and summer. Nature 360: rarely plunge-dive (and then from heights of only 0.3- 336-337. 0.5 m (M. J. Whitehouse,pers. comm.), mainly making ASHMOLE,N. P. 1971. Seahird ecology and the ma- surface dives (Harper et al. 1985) so overestimation tine environment, p. 224-286. In D. S. Famer, J. of dive depth is unlikely from this source. Wanless et R. King, and K. C. Parkes teds.], Avian biology, al. (199 1) suggestedthat gaugeson European Shags Vol. 1. Academic Press, New York. Phalacrocorax aristotelis not recovered within 24 hr BROWN,R.G.B., W.R.P. BOURNE,AND T. R. WAHL. -gave less nlausible (overestimated) results. In White- 1978. Diving- by_ shearwaters.Condor 80: 123-l 25. chinned Petrels, there was an increase in maximum BROWN, R.G.B., S. P. BARKER,D. E GASKIN,AND M. recorded dive depth with deployment duration, but R. SANDEMAN. 1981. The foods of Great and this was small and could well simply reflect the greater Sooty ShearwatersPufinus gravis and P. griseus likelihood of recordingdeeper dives the longerthe gauge in eastern Canadian waters. Ibis 123:19-30. is in operation. Overall, even if overestimating dive BURGER,A. E. 1991. Maximum diving depths and depth by lo%, my data indicate that diving White- underwaterforaging in alcids and penguins.In W. chinned Petrels regularly attain 5 m and can reach 12 A. Montevecchi and A. J. Gaston [eds.], Studies m. of high latitude seabirds. 1. Behavioural energetic White-chinned Petrels observed making wing-pro- and oceanographicaspects of seabirdfeeding ecol- pelled surface dives had dive durations that averaged ogy. Can. Wildl. Serv., Occas. Pap. No. 68:9-15. 2.4 set (SD 2.0, range 0.4-6.3 set, n = 14) (M. J. BURGER,A. E., AND R. P. WILSON. 1988. Capillary- Whitehouse, pers. comm.). Another observerreported tube depth gaugesfor diving : an assess- similar dives lasting at least 5 set (J. R. Ashford, pers. ment of their accuracyand applicability. J. Field comm.). These records probably substantially under- Omithol. 59:345-354. estimate the breath-hold capacity of White-chinned CROXALL, J. P., Y. NAITO,A. KATO, P. ROTHERY,AND Petrels but if they can travel at 2 m set-l (as typically D. R. B~GGS. 1991. Diving patterns and per- recorded for wing-propelled penguins(Kooyman et ai. formance in the Antarctic Blue-eyed Shag Phal- 1992) and alcids (Swennen and Duiven 1991) under- acrocorax atriceps. J. Zool. (Lond.) 225: 177-199. water), then on a 6 set dive they could reach 6 m, CROXW, J. P., D. R. B~GGS, A. KATO, Y. NAITO, Y. which is the averagedepth recordedby the birds in the WATANUKI,AM) T. D. WILLIAMS. 1993. Diving study. pattern and performance in the Marconi Thus, there is little reason to believe that the data Eudyptes chrysolophus. J. Zool. (Lond.) 230:31- reported here are not representativeof the diving abil- 47. ities of White-chinned Petrels. The distribution of CROXALL, J.P., A.J. Hw,H.J. HILL, A. W. NORTH, maximum depthsof White-chinned Petrelsis very sim- AND P. G.’ RODHOUSE. In press. The food and ilar to the rangeof dive depths measuredfor the Light- feeding ecology of the White-chinned Petrel Pro- mantled Sooty AlbatrossPhoebetriapalpebrata (Prince cellaria aequinoctialis at South Georgia. J. Zool. et al. 1994), the speciesmost similar in body propor- (Lond.) tions to White-chinned Petrels (Pennycuick 1982, Pen- HALL,A. J. 1987. The breedingbiology of the White- nycuicket al. 1984).That all birds in the samplereached chinned Petrel Procellaria aequinoctialis at South about a depth of 3 m or more suggeststhat suchdiving Georgia. J. Zool. (Lond.) 2 12:605-6 17. may be a regular part of foraging behavior in White- HARPER,P. C., J. P. CROXALL,AND J. COOPER. 1985. SHORT COMMUNICATIONS 1113

A guide to foragingmethods usedby marine birds Pelecanoides georgicus at Bird Island, South Geor- in Antarctic and seas. BIOMASS gia. Antarct. Sci. 4:433434. Handbook 24:1-22. Pnt~cn, P. A., N. Hum, ANDH. WEIMERSKIRCH.1994. KCXXMAN, G. L., Y. CHEREL,Y. LE MAHO, J. P. Diving depths of albatrossesat South Georgia and CROXALL,P. H. THORSON,V. RIJXXJX,AND C. A. Macauarie Islands. Antarct. Sci. 6:353-354. KCXXMAN. 1992. Diving behavior and energet- SKIRA,I. J. 1979. Underwater feedingby Short-tailed its during foraging cyclesin King Penguins,Ecol. Shearwaters.Emu 79:43. Monogr. 62:143-163. S~ENNEN,C., AND P. DUIVEN. 1991. Diving speed KURODA,M. 1954. On the classificationand phylog- and food-size selection in Common Guillemots eny ofthe Tubinaires, particularlythe shear- Uria aalge. Neth. J. Sea Res. 27:191-196. waters (). Herald Co.. Tokvo. WANLESS,S., A. E. BURGER,AND M. P. HARRIS. 1991. P-cut&, C. J. ‘1982. The kight -of petrels and Diving depths of ShagsPhalacrocorax aristotelis (Procellariiformes), observedin South breeding on the Isle of May. Ibis 133:3742. Georgia and its vicinity. Phil. Trans. Roy. Sot. WILSON.R. P.. ANDM.-P. T. WILSON. 1988. Foraeine Lond. B 300:75-106. behaviour in four sympatric cormorants.J. Ammy Prr~~~cutcrc,C. J., J. P. CROXALL,AND P. A. PRINCE. Ecol. 57:943-955. 1984. Scalingof foraging radius and growth rate WOOD, K. A. 1993. Feeding behaviour, offal pref- in petrels and albatrosses(Procellariiformes). Or- erencesand tarsus shape of Pufinus shearwaters nis Stand. 15145-154. off central New South Wales. Notomis 40: 123- PRINCE,P. A., ANDM. JONES. 1992. Maximum dive 127. depths attained by South Georgia

The Condor 96:1113-l 114 Q The CooperOmithologkal Society 1994

MULTIPLE CASES OF POLYGYNY IN THE BLACK-CAPPED CHICKADEE: A POSSIBLE ADVANTAGE TO THE PRIMARY FEMALE ’

JANINER. CLEMMONS Department of Zoo&y, University of Wisconsin, Madison. WI 53706

Key words: Polygamy; polygyny; Black-capped In both cases,the nests of the primary females were Chickadee; Parus atricapillus;female choice. depredated, and the primary females subsequently usurpedthe nests of the secondaryfemales. Secondary The Black-cappedChickadee, Parus atricapillus, is al- females were not seen in the nesting area after usur- most strictly monogamouswith only one reported case pation. The third casewas discoveredin a nearbywoods of polygyny (Smith 1967, Smith 1991) and two re- after the eggsof the secondaryfemale were laid. This ported casesof polyandry (Waterman et al. 1989, How- nest resided within the defended area of the male, as itz 1991). Here I report several casesof bigyny occur- indicated by his responseto playbacksoffee-bee song. ring during one breeding seasonwithin a small study The nest of the primary female fledged, and the nest area. The primary female was identified as the first of the secondaryfemale was depredatedafter hatching. female to nest on the territory. The degree to which secondaryfemales were toler- In 1992, there were three cases in which female ated on the territories was unclear,but they were prob- chickadees constructed nests on territories of mated ably excluded from the nest vicinity of the primary pairs in the Picnic Point area of the University of Wis- female. In one case the primary female was once ob- consin-Madison. Two casesoccurred in an area with served to chase the secondaryfemale a short distance about ten nesting pairs. The males assisted primary from the nest but not completely off the territory. In females with excavation of the nestingcavities, where- another case, the two females and the male foraged as secondaryfemales excavated alone. Copulation with together without aggressionon the territory but away the secondaryfemale while the primary female incu- from the nest site of the primary female prior to egg bated was observed in one case. In the second case, laying. The primary female was once observedto sup- althoughcopulation with the secondaryfemale was not plant the secondaryfemale who was peering into the observed, the male defended her nestingarea, as dem- primary female’s nesting cavity. Aggression is also onstrated when he sang“fee-bee” in responseto play- known to occur between resident females in polygy- backsoffee-bee songwithin 20 m of her nestingcavity. nous species(Searcy 1988, Yasukawa et al. 1992). Why polygyny was common in the Madison study area during the breeding season of 1992 is unclear. There were no other reported casesof polygyny in the ’ Received 27 July 1994. Accepted 1 August 1994. previous three years of the study. In the related Blue