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Showing papers in "Ostrich in 1980"


Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: McLachlan et al. as discussed by the authors investigated the seasonal abundance, biomass and feeding of shore birds on sandy beaches in the Eastern Cape, South Africa, and found that the dominant birds were the Southern Blackbacked Gull Larus dominicanus, Black Oystercatcher Haematopus moquini, Whitefronted Sandplover Charadrius marginatus and Sanderling Calidris alba.
Abstract: Summary McLachlan, A., Woodridge, T., Schramm, M. & Kuhn, M. 1980. Seasonal abundance, biomass and feeding of shore birds on sandy beaches in the Eastern Cape, South Africa. Ostrich 51:44-52. The numbers of birds on three Eastern Cape sandy beaches were monitored monthly over one year during 1977/78. Dominant among 17 species were the Southern Blackbacked Gull Larus dominicanus, Black Oystercatcher Haematopus moquini, Whitefronted Sandplover Charadrius marginatus and Sanderling Calidris alba. These four species made up 95% of bird numbers and their respective biomass values were 78 652, 7 695, 578 and 3 116 kJ/km shoreline. Total food consumption for these species, calculated on the basis of estimated standard metabolic rates, was 4 159 394, 521 149, 76 768 and 363 053 kJ/km respectively. Food composition and feeding behaviour are also discussed and the total quantity of intertidal macrobenthic animals consumed by birds estimated.

54 citations


Journal ArticleDOI
01 Dec 1980-Ostrich
TL;DR: Bashoff et al. as mentioned in this paper reviewed the past and present distribution and status of the Cape Vulture Gyps coprotheres in the Cape Province according to four time periods from before 1905 to the present day and concluded that drastic decline in the game herds, particularly during the 19th century, together with the recent changes in stock farming, are the most important factors determining the numbers and distribution of Cape Vultures.
Abstract: Summary Boshoff, A. F. & Vernon, C. J. 1980. The past and present distribution and status of the Cape Vulture in the Cape Province. Ostrich 51:230-250. Because of the apparent decline in range and numbers of the Cape Vulture Gyps coprotheres in the Cape Province, the distribution and status of this species were reviewed according to four time periods from before 1905 to the present day. All available information was assembled, assessed and interpreted. It is apparent that, although the present decline is real, the population has undergone previous fluctuations. The magnitude, nature and possible causes of the fluctuations are discussed. It is postulated that the drastic decline in the game herds, particularly during the 19th century, together with the recent changes in stock farming, are the most important factors determining the numbers and distribution of Cape Vultures. Direct and indirect persecution also have a detrimental effect on vulture populations. Farmers' attitudes towards vultures are mentione...

35 citations


Journal ArticleDOI
01 Jun 1980-Ostrich
TL;DR: 22 species are identified from three Miocene and two Pleistocene localities, 20 being additions to the existing list, and a new touraco Apopempsis africanus sp.
Abstract: Summary Harrison, C. J. O. 1980. Fossil birds from Afrotropical Africa in the collection of the British Museum (Natural History). Ostrich 51:92-98. Although it has a rich avifauna, few fossil birds are know from Africa south of the Sahara. In the present paper 22 species are identified from three Miocene and two Pleistocene localities, 20 being additions to the existing list. A new touraco Apopempsis africanus sp. nov. is described from the Lower Miocene of Songhor, Kenya; and from the same period on Rusinga Island, Kenya, a new stork Ciconia minor sp. nov., in addition to a small flamingo, a hawk and a francol-in. There is evidence of a bustard and a Ciconia stork from the Middle Miocene of Maboko Island, Kenya. In the Pleistocene nine species are listed for Olduvai, Tanzania, and seven for Broken Hill, Zambia. There is some evidence of a shared Afro-tropicai/Palaearctic fuana in the Miocene, and of a larger inland lake bird fauna in the Early Pleistocene of Olduvai, but the Broken Hill material is purel...

30 citations


Journal Article
11 Feb 1980-Ostrich

25 citations


Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: Males were larger than females in all dimensions but were otherwise similar in external appearance and external features of the head and the voice could be used to differentiate adults, subadults and juveniles in the field.
Abstract: Summary Burger, A. E. 1980. Sexual size dimorphism and aging characters in the Lesser Sheathbill at Marion Island. Ostrich 51:39-43. Mass and linear dimensions of adult, subadult and juvenile Lesser Sheathbills Chionis minor at Marion Island are given. Males were larger than females in all dimensions but were otherwise similar in external appearance. The larger size of males is attributed to selection favouring male dominance in aggressive territorial encounters. External features of the head and the voice could be used to differentiate adults, subadults and juveniles in the field.

24 citations


Journal ArticleDOI
01 Dec 1980-Ostrich
TL;DR: Bones were collected from 16 nests of Crowned Eagles Polemaetus coronatus and three of these nests were observed from hides to give some idea of the spectrum of prey animals taken and reveal differences from nest to nest.
Abstract: Summary Jarvis, M. J. F., Currie, M. H. & Palmer, N. G. 1980. Food of Crowned Eagles in the Cape Province, South Africa. Ostrich 51:215-218. Bones were collected from 16 nests of Crowned Eagles Polemaetus coronatus and three of these nests were observed from hides. The bone remains give some idea of the spectrum of prey animals taken and reveal differences from nest to nest. A total of 598 distinct prey animals were identified. The Rock Hyrax Procavia capensis formed 42%, Blue Duiker Cephahphus monticola 16%, juvenile Bushbuck Tragelaphus scriptus 12% Vervet Monkeys Cercopithecus pygerytkrus 8% and juvenile bovids 6% Although 15 out of 16 nests showed Rock Hyrax remains, Blue Duiker were found at only 10 nests and juvenile Bushbuck at nine. Juvenile bovids were mainly domestic lambs and came from 10 nests, but never comprised more than 16% of the total prey animals at any one nest. Some farmers have found ways of stopping predation on lambs without having to destroy the eagles.

23 citations


Journal ArticleDOI
19 Aug 1980-Ostrich
TL;DR: The breeding biology of the Subantarctic Skua Catharacta antarctica lonnbergi was studied in two austral summers at Marion Island and chicks in one- and two-chick broods had similar growth rates until 50 days after hatching when chicks reared singly were heavier.
Abstract: Summary Williams, A. J. 1980. Aspects of the breeding biology of the Subantarctic Skua at Marion Island. Ostrich 51:160-167. The breeding biology of the Subantarctic Skua Catharacta antarctica lonnbergi was studied in two austral summers at Marion Island. Eggs were laid between 23 October and 19 December. The clutch size was one (6%) or two (94%) eggs. The laying interval was two (20%) or three (80%) days and the incubation period was 29 days. Chicks could fly at 50–65 days after hatching. Chicks from first and second hatched eggs in the same brood had similar growth rates. Chicks in one- and two-chick broods had similar growth rates until 50 days after hatching when chicks reared singly were heavier. Egg mortality was 15,8%, chick mortality was 34,8% and the overall breeding success was 50,9%. The results are discussed in comparison with previous studies of Subantarctic and South Polar C. maccormicki Skuas.

16 citations


Journal ArticleDOI
01 Jun 1980-Ostrich
TL;DR: Macdonald et al. as mentioned in this paper studied the ecology of the Fiscal Shrike Lanius collaris in southern Ghana in order to compare its ecology there with that in southern Africa.
Abstract: Summary Macdonald, M. A. 1980. The ecology of the Fiscal Shrike in Ghana, and a comparison with studies from southern Africa. Ostrich 51:65-74. The Fiscal Shrike Lanius collaris was studied in southern Ghana in order to compare its ecology there with that in southern Africa. The bird was found mainly in the damper coastal areas and usually in habitats created by man. Feeding behaviour is described. Food consisted mainly of a wide variety of insects. Territories were small at around 0,6 ha. Most nests were built 1,8-2,4 m from the ground, and eggs were laid from December to October. Moult appeared to take place in September to November when breeding activity was low. The normal and maximum clutch was three eggs. At most, 10–17% of clutches produced fledged young. Most losses were probably caused by predators. Two successful broods per pair were reared annually. Post-fledging survival of the young was high, and they remained on the parental territory for 5–7 months. Contrasts between the breeding biology in...

12 citations


Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: The Roseate Tern Sterna dougallii population in Algoa Bay is the largest and now possibly the only breeding population in southern Africa as discussed by the authors, and it has a world wide distribution and is in no immediate danger of extinction.
Abstract: Summary Randall, R. M. & Randall, B. M. 1980. Status and distribution of the Roseate Tern in South Africa. Ostrich 51:14-20. The Roseate Tern Sterna dougallii population in Algoa Bay is the largest, and now possibly the only breeding population in southern Africa. The two mainland breeding sites at Cape Recife and Kommetjie have been deserted, and in recent years the last remaining breeding site outside Algoa Bay may have been abandoned. Consequently the present estimate of between 70 and 80 breeding pairs in Algoa Bay may represent the entire southern African population. The decline in numbers from hundreds in 1937 is ascribed to human interference. Although the species is rare and endangered in southern Africa, it has a world wide distribution and is in no immediate danger of extinction.

11 citations


Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: Stock predation by territorial, mated Martial Eagles was only 8% in this study, with some, at least, probably taken as carrion, and the validity of the analysis of prey remains collected from or below eagle nests is discussed.
Abstract: Summary Boshoff, A. F. & Palmer, N. G. 1980 Macro-analysis of prey remains from Martial Eagle nests in the Cape Province. Ostrich 51:7-13. A total of 346 prey items, collected from nine Martial Eagle Polemaetus bellicosus nests in the Cape Province, was analyzed. The importance of e.g. Leporidae and Viverridae in the prey spectrum is emphasized. Young domestic small-stock appear to stand at least as much chance of predation by large eagles as does the natural prey of these birds. Nevertheless stock predation by territorial, mated Martial Eagles was only 8% in this study, with some, at least, probably taken as carrion. The validity of the analysis of prey remains collected from or below eagle nests is discussed.

10 citations


Journal ArticleDOI
01 Sep 1980-Ostrich
TL;DR: Three nesting territories of Bateleurs Terathopius ecaudatus were studied at Essexvale, Zimbabwe, from 1962 to 1976, and this paper augments previously published observations.
Abstract: Summary Steyn, P. 1980. Breeding and food of the Bateleur in Zimbabwe (Rhodesia). Ostrich 51:168-178 Three nesting territories of Bateleurs Terathopius ecaudatus were studied at Essexvale, Zimbabwe, from 1962 to 1976, and this paper augments previously published observations. Further details of breeding biology are given, and these show close similarities to those of snake eagles Circaetus spp. In 22 pair-years at Essexvale 17 young were reared, or 0,77 young/pair/year, and if combined with five years' observation at another nest in Zimbabwe then the figure is 0,81. A total of 238 prey items was collected, 47,5% birds, 42,0% mammals, 8,0% reptiles and 2,5% fish, and comparisons are made with three other studies of Bateleur prey. Evidence for direct predation is considered; Bateleurs kill many species of birds and a variety of mammals, but reptiles are not a significant aspect of diet. Carrion appears to be most important in the diet of immatures. The Bateleur has undergone a serious decline in South Afric...

Journal ArticleDOI
28 Dec 1980-Ostrich
TL;DR: Density, mensural data and moult are discussed and compared with findings from the Cape Province, and identification criteria for second-year birds are given.
Abstract: Summary Schmitt, M. B., Baur, S. & Von Malitz, F. 1980. Observations on the Steppe Buzzard in the Transvaal: Ostrich 51:151-159. During a three year study 247 Steppe Buzzards Buteo buteo vulpinus were captured in the Transvaal, South Africa. Density, mensural data and moult are discussed and compared with findings from the Cape Province. Linear density is 7,3 times lower in the Transvaal as compared with the Cape. Identification criteria for second-year birds are given. Second-year birds moult primaries descendently and symmetrically, secondary moult is mainly ascendent and symmetrical, tail moult irregular but symmetrical. Adult birds moult irregularly. Recorded food items are listed.

Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: Wilson's Widowfinch Vidua wilsoni and the Pintailed Whydah V. macroura were both common, the former in residential areas and the latter on open ground, and both bred in the wet season and moved out of the area from October to December.
Abstract: Summary Macdonald, M. A. 1980. Observations on Wilson's Widowfinch and the Pintailed Whydah in southern Ghana, with notes on their hosts. Ostrich 51:21-24. Information on the two viduines occurring at Cape Coast, southern Ghana, was collected casually between 1975 and 1978. Wilson's Widowfinch Vidua wilsoni and the Pintailed Whydah V. macroura were both common, the former in residential areas and the latter on open ground. Both bred in the wet season and moved out of the area from October to December. Widow-finches during the dry season formed flocks which contained a small but variable proportion of recognizable adult males. Flocks broke up from March, and in the breeding season almost all groups had only a single adult male. Lagonosticia rufopicta was recorded as a biological host of the widowfinch. Estrilda troglodytes, E. melpoda and Lonchura cucullata were recorded as hosts fo the whydah. The whydahs (but not the widowfinches) were usually reared with the host young, and host productivity was reduced.

Journal ArticleDOI
01 Sep 1980-Ostrich
TL;DR: Macdonald et al. as discussed by the authors reported that the Diederik Cuckoo Chrysococcyx caprius was largely separated from its three congeners (Kiaas's, Emerald and Yellowthroated Cuckoos) by habitat.
Abstract: Summary Macdonald, M. A. 1980. Observations on the Diederik Cuckoo in southern Ghana. Ostrich 51:75-79. Casual observations were made on the Diederik Cuckoo Chrysococcyx caprius at Cape Coast in southern Ghana from 1975 to 1978. The Diederik was largely separated from its three congeners (Kiaas's, Emerald and Yellowthroated Cuckoos) by habitat. Most food was taken from or close to the ground, and consisted mainly of caterpillars or similar larvae. Diederiks were almost absent from the area during September and October. The main host colony of Ploceus weavers was attended by up to five males and three females simultaneously during the wet season. Apparent laying attempts observed between March and July are described. Usually the female removed a host egg and spent between 3 and 9 s in the nest. The Spottedbacked Weaver Ploceus cucullalus was recorded as a biological host. The contrast between the social systems described from southern Africa and that found at Cape Coast is discussed and a link with the soc...

Journal ArticleDOI
01 Dec 1980-Ostrich
TL;DR: Brief field studies of the Green Barbet Stactolaema olivacea in coastal Kenya, with emphasis on vocalizations, document its social behaviour, including communal roosting of four birds in a cavity.
Abstract: Summary Short, L.L. & Horne, J. F. M. 1980, Vocal and other behaviour of the Green Barbet in Kenya. Ostrich 51:219–229. Brief field studies of the Green Barbet Stactolaema olivacea in coastal Kenya, with emphasis on vocalizations, document its social behaviour, including communal roosting of four birds in a cavity. Green Barbets are aggressive, interacting strongly with a number of species. Erecting of the crown feathers, cocking of the tail, and woodpeckerlike swinging movements characterize displays. Wing Flutters and audible Bill Wiping are visual-auditory displays. Vocalizations include the Grating Call, Kek Call, Chuk Call and Chowp Call. These are agonistic and agonistic-reproductive in function. The Chowp Call comprises the song, used in simultaneous singing and duetting.

Journal ArticleDOI
01 Jun 1980-Ostrich
TL;DR: The pattern and rate of the complete moult cycle in the Redbilled Oxpecker Buphagus er ythrorhynchus is described and the two body moult cycles correspond with the moult of the differentiated inner secondaries.
Abstract: Summary Stutterheim, C. J. 1980. Moult cycle of the Redbilled Oxpecker in the Kruger National Park. Ostrich 51:107-112. This paper describes the pattern and rate of the complete moult cycle in the Redbilled Oxpecker Buphagus er ythrorhynchus. The average duration of primary moult in adult birds was 340 days and the mean time to replace a primary feather was calculated as 34 days. The moult of the secondaries is initiated at two points, at the first secondary and at the innermost secondary. Secondary moult takes seven months. The differentiated inner secondaries moult in the normal middle/inner/outer passeriform fashion. The rectrices moulted only once annually. The two body moult cycles correspond with the moult of the differentiated inner secondaries. First-year birds undergo a partial postjuvenile feather replacement at three months of age.

Journal ArticleDOI
17 Aug 1980-Ostrich
TL;DR: Evaluation of the applicability of fluorescent polyvinyl leg streamers for colour-marking Redbilled Queleas, Spottedbacked Weavers, and Palm Weavers in West and East Africa found the method has possible use in movement studies and control operations for these and other bird pests.
Abstract: Summary Bruggers, R. L. 1980. Marking ploceid weavers with leg streamers. Ostrich 51:193-197. Laboratory and field trials were conducted in both West and East Africa to evaluate the applicability of fluorescent polyvinyl leg streamers for colour-marking Redbilled Queleas, Spottedbacked Weavers, and Palm Weavers, important bird pests to African cereal crops. Under laboratory conditions birds retained their streamers from 8 to 13 weeks. In the field, Spottedbacked Weavers which were marked late in colony development continued normal nesting activities, but those marked early tended to desert the colony. Spottedbacked Weavers seemed less irritated by the streamers than Redbilled Queleas. The marking method has possible use in movement studies and control operations for these and other bird pests.


Journal ArticleDOI
01 Dec 1980-Ostrich
TL;DR: Morant, P. D. as mentioned in this paper presented a report on ringing activities for southern Africa from July 1977 to June 1978, which is a continuation of the trend established by emphasis being placed on project-oriented rather than indiscriminate ringing.
Abstract: Summary Morant, P. D. 1980. Twenty-first ringing report for southern Africa. Ostrich 51:204-214. A report on ringing activities for southern Africa from July 1977 to June 1978 is presented. A total of 16 830 birds of 346 species was ringed. This is a continuation of the trend established by emphasis being placed on project-orientated rather than indiscriminate ringing.

Journal ArticleDOI
01 Sep 1980-Ostrich
TL;DR: Plumage characters of immatures are given, with their probable duration, age being determined by skull pneumatization, retrapping, moult and the breeding season, for the first six species, and some data are given on habits.
Abstract: Summary Hanmer, D. B. 1980. Mensural and moult data of eight species of kingfisher from Mozambique and Malawi. Ostrich 51:129-150. Wing length, weight and moult data are given for the Malachite Kingfisher Alcedo crisrata, Pygmy Kingfisher Ispidina picta, Woodland Kingfisher Halcyon senegalensis, Greyhooded Kingfisher H. leucocephala, Brownhooded Kingfisher H. albiventris, Striped Kingfisher H. chelicuti, Pied Kingfisher Ceryle rudis and Giant Kingfisher C. maxima from Mopeia (Mocambique) and Nchalo (Malaŵi). Plumage characters of immatures are given, with their probable duration, age being determined by skull pneumatization, retrapping, moult and the breeding season, for the first six species. Moulting seasons, immature age at moult, the duration of primary moult, its relation to the breeding season and the sequence of moult in remiges and rectrices are given for A. cristala and I. picta and discussed for the Halcyon kingfishers. Some data are given on habits.

Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: Anthony et al. as discussed by the authors found that the only food item regurgitated by nestlings was the soft parts of the snail Lanistes ovum which abounded in the swampy areas near the heronry.
Abstract: Summary Anthony, A. J. & Sherry, B. Y. 1980. Openbill Storks breeding in the southeastern lowveld of Zimbabwe Rhodesia. Ostrich 51:1-6. Openbill Storks Anastomus lamelligerus bred in the Gonarezhou National Park at Tam-boharta pan between January and June 1974 and again in 1975. Two breeding cycles occurred during the 1974 season. The storks nested in a mixed heronry in Acacia albida trees which were at the time rooted in a flooded alluvial pan. In 1974, 65 of 165 nests in the colony belonged to Openbills and in 1975, 78 of 130 nests belonged to Openbills. Successful breeding activity appeared to be associated with excessive rains, resulting in submerged trees in which to nest and abundant snails on which to feed. Clutch size was three to four eggs and hatching was markedly asynchronous. The only food item regurgitated by nestlings was the soft parts of the snail Lanistes ovum which abounded in the swampy areas near the heronry.

Journal ArticleDOI
01 Jun 1980-Ostrich
TL;DR: Jones et al. as discussed by the authors found that post-nuptial and post-juvenile moults of the Greyhooded Kingfisher Halcyon leucocephala took place in northern Nigeria between May and November (the rainy season) after migration from the southern breeding areas.
Abstract: Summary Jones, P. J. 1980. The timing of wing moult in the Greyhooded Kingfisher in Nigeria. Ostrich 51:99-106. The post-nuptial and post-juvenile moults of the Greyhooded Kingfisher Halcyon leucocephala took place in northern Nigeria between May and November (the rainy season) after migration from the southern breeding areas. Moult of individual birds lasted between 92 and 176 days, those starting moult latest (mostly juveniles) moulting fastest. This variation may be related to food availability during moult; those starting early do so before the rainy season begins in the north and before insect numbers increase, whereas those moulting later do so during the full flush of rainy season insect availability. This variability appears to be adaptive in allowing the complete moult to be fitted into the period remaining between the end of the breeding season, which is variable, and the southward migration in the early dry season, whose timing is relatively fixed.

Journal ArticleDOI
01 Mar 1980-Ostrich
TL;DR: The characters identifying immatures and the probable length of time these are retained, are given with reference to skull pneumatization, retrapped birds, moult or the breeding season for M. pusillus and M. boehmi.
Abstract: Summary Hanmer, D. B. 1980. Mensural and moult data on six species of bee-eater in Mocambique and Malawi. Ostrich 51:25-38. Wing length, weight and moult data are given for the Little Bee-eater Merops pusillus, Boehm's Bee-eater M. boehmi, European Bee-eater M. apiaster, Bluecheeked Bee-eater M. persicus, Carmine Bee-eater M. nubicus and Swallowtailed Bee-eater M. hirundineus from Mopeia (Mocambique) and Nchalo (Malaŵi). The characters identifying immatures and the probable length of time these are retained, are given with reference to skull pneumatization, retrapped birds, moult or the breeding season for M. pusillus and M. boehmi. Culmen length is given with reference to the breeding season in adults and age in immatures for M. pusillus and M. boehmi. Weights are compared with some published for other parts of Africa. The months during which moult occurred are given. Duration of primary moult and its relation to the breeding season, as well as the order of moult in remiges and rectrices and the age at w...

Journal Article
02 Jul 1980-Ostrich

Journal ArticleDOI
01 Dec 1980-Ostrich
TL;DR: The breeding biology of the Rock Pigeon Columba guinea was studied for three seasons from 1972 to 1975 at the University of Cape Town, southwestern Cape, South Africa.
Abstract: Summary Elliott, C. C. H. & Cooper, J. 1980. The breeding biology of an urban population of Rock Pigeons Columba guinea. Ostrich 51:198-203. The breeding biology of the Rock Pigeon Columba guinea was studied for three seasons from 1972 to 1975 at the University of Cape Town, southwestern Cape, South Africa. Nests were visited at approximately weekly intervals. The breeding season (September to February) coincided with the end of the winter rainy season and the presence of cereal crops. Clutch size was two eggs in 99% of cases. Mean incubation period was 14,8 days. Incubation was shared as two continuous shifts per day. Growth rate was similar to that in other studies. The mean nestling period was 23,6 days. Second broods after the successful departure of chicks were frequent, the interval between nest departure and re-laying being as little as five days. Hatching success was 66%, chick rearing success 83% and overall breeding success 49%, similar to other Columba pigeons. It is suggested that the producti...


Journal ArticleDOI
01 Jun 1980-Ostrich
TL;DR: From 1974–1976, Laughing Doves Streptopelia senegalensis raised an observed total of 436 young in 619 nest attempts, giving a breeding success of 0,70 young per pair nest attempt, or an overall success of0,35 young per egg.
Abstract: Summary Dean, W. R. J. 1980. Population, diet and the annual cycle of the Laughing Dove at Barber-span, Part 4: Breeding data and population estimates. Ostrich 51:80-91. From 1974–1976, Laughing Doves Streptopelia senegalensis raised an observed total of 436 young in 619 nest attempts, giving a breeding success of 0,70 young per pair nest attempt, or an overall success of 0,35 young per egg. Breeding success, estimated by computing the probability of survival of an egg through the incubation period, and of a chick through the nestling period suggest that the breeding success is about 0,33 young per egg. Nests were found in every month of the year, though there was a tendency for breeding to be concentrated during the late rainy season and the dry season. The mean annual population size of the Laughing Dove in the study area was estimated at 221 adults and juveniles by one method and at 237 adults and juveniles by another method. The number of young produced each year is correlated with the estimated popul...