Breeding Biology and Current Status of the Grey Kangaroo, Macropus Fulginosus Fulginosus, of Kangaroo Island, South Australia.

1976 ◽  
Vol 24 (2) ◽  
pp. 169 ◽  
Author(s):  
WE Poole
Keyword(s):  
South Australia ◽  
Growth Curves ◽  
Current Status ◽  
First Year ◽  
Grey Kangaroo ◽  
Western Grey Kangaroo ◽  
Early Exploration ◽  
Males And Females ◽  
Sexually Mature ◽  
Length Of Gestation

A distinct large dark brown kangaroo first attracted the attention of Europeans during the early exploration of Kangaroo I. in 1802-03. Although specimens were collected and the kangaroo ade- quately described, its subsequent taxonomic history was confused, and its origin long held to be Tasmania. This fallacy was not corrected until 1923-24. Subsequently the kangaroo has been re- cognized as a subspecies of the western grey kangaroo. Reproduction and growth of the young were examined in both wild and captive kangaroos. Males and females became sexually mature from age 20 months, the oestrous cycle was 34.6+ 3.2 (SD) days and the length of gestation 30.8 � 1.8 days. Births occurred on all months of the year but were more frequent in summer. The pouch life was just over 300 days, while loss of such young usually resulted in return to oestrus after an interval of 6.3 � 0.1 days. Disparity in sex ratio of the young was not significant. During their first year, young were measured each week. Growth curves are presented and linear or quadratic regressions fitted where applicable, together with 95% confidence limits.

scholarly journals Notes on the growth and biology of the prawn Spirontocaris lilljeborgii (Danielssen)

1954 ◽  
Vol 33 (3) ◽  
pp. 739-747 ◽  
Author(s):  
R. B. Pike
Keyword(s):  
Incubation Period ◽  
Small Proportion ◽  
Egg Laying ◽  
First Year ◽  
Dioecious Species ◽  
Eye Pigmentation ◽  
Males And Females ◽  
Second Year ◽  
Sexually Mature

SummarySpirontocaris lilljeborgii is a dioecious species and no protandrous hermaphrodites have been seen.The majority of males become sexually mature in the first year (7–9 months). Some of these may die after fertilizing the females and the majority die after fertilizing the females for a second year (18 months old).Only a small proportion of the females breed in their first year, all breed during their second year and a few appear to live for a third year.A first-year female lays from 130 to 160 eggs, and the usual output of a second-year female is from 450 to 650 eggs.Egg laying begins at the end of November and hatching is complete by the end of March.The total incubation period is about 90 days. Eye pigmentation first appears at about half the incubation period (47 days).Juveniles can be distinguished as males and females by the shape of their pleopods within 4–6 months of hatching.

Reproduction in Antechinomys laniger ('spenceri' Form) ( Marsupialia : Dasyuridae): Field and Laboratory

1984 ◽  
Vol 11 (3) ◽  
pp. 481 ◽  
Author(s):  
PA Woolley
Keyword(s):  
Breeding Season ◽  
Oestrous Cycle ◽  
Average Rainfall ◽  
Proximate Factor ◽  
Breeding Condition ◽  
Males And Females ◽  
Sexually Mature ◽  
Length Of Gestation

Antechinomys laniger is polyoestrous, and animals from Sandringham Station in south-western Queensland are in breeding condition from midwinter to midsummer. Laboratory observations suggest that photoperiod may be the proximate factor controlling the timing of the breeding season. Females enter oestrus up to six times during the season, and as the season progresses the length of the oestrous cycle decreases. The estimated length of gestation is 12 days or less. Females may rear up to six young. The young are weaned when about 3 months old and become sexually mature at 11.5 months. Both males and females are potentially capable of breeding in more than one season. Higher than average rainfall may have led to a decline in the numbers of A. laniger on Sandringham Station.

scholarly journals Age, growth, maturity, longevity and natural mortality of the shortfin mako shark (Isurus oxyrinchus) in New Zealand waters

2006 ◽  
Vol 57 (2) ◽  
pp. 143 ◽  
Author(s):  
S. D. H. Bishop ◽  
M. P. Francis ◽  
C. Duffy ◽  
J. C. Montgomery
Keyword(s):  
Fork Length ◽  
Growth Curves ◽  
Growth Patterns ◽  
Birth Date ◽  
First Year ◽  
Natural Mortality ◽  
Relative Growth ◽  
Mako Shark ◽  
Shortfin Mako ◽  
Males And Females

Shortfin mako sharks were aged by counting growth bands in sectioned vertebrae (n = 256), and assuming annual band-pair deposition. No systematic ageing bias was present and count precision was high. 0+ juveniles were identified from length–frequency plots and assigned ages based on a theoretical birth date of 1 October and their date of capture. A Schnute generalised growth model fitted to the combined vertebral and 0+ data described the growth patterns best. Shortfin makos grow very rapidly initially, increasing by ~39 cm fork length in their first year. Thereafter, males and females grow at similar but slower rates until about age 7 years, after which the relative growth of males declines. Longevity estimates were 29 and 28 years for males and females respectively. Natural mortality (M) is probably in the range of 0.10–0.15. Median ages at maturity were 7–9 years for males and 19–21 years for females. Comparisons of growth curves reported here and elsewhere suggest no regional differences in growth rates. The shortfin mako is a late-maturing species with moderate longevity and low natural mortality. With these life history characteristics and an unknown stock size and structure worldwide, management should be of a precautionary nature.

Disarticulation of kangaroo skeletons in semi-arid Australia

2001 ◽  
Vol 49 (6) ◽  
pp. 615 ◽  
Author(s):  
Elizabeth H. Reed
Keyword(s):  
South Australia ◽  
Morphological Features ◽  
Long Bones ◽  
Fossil Bone ◽  
Caudal Vertebrae ◽  
Grey Kangaroo ◽  
Western Grey Kangaroo ◽  
African Ungulates ◽  
Semi Arid

This study presents a natural disarticulation sequence for the western grey kangaroo, Macropus fuliginosus, from surface bone assemblages in semi-arid South Australia. Comparison with published disarticulation sequences for African ungulates reveals significant differences in the kangaroo sequence, including earlier disarticulation of the forelimb long bones, carpus and cervical elements, and later disarticulation of the caudal vertebrae, and hindlimb long bones. These differences closely correspond to anatomical and morphological features of the kangaroo skeleton. The results of this study suggest that anatomy plays an important role in disarticulation and may ultimately control the process even following utilisation by predators and scavengers. The disarticulation sequence reported here has useful applications for the interpretation of fossil bone assemblages containing both extant and extinct kangaroos.

Growth of Grey Kangaroos and the Reliability of Age Determination from Body Measurements II.* The Western Grey Kangaroos, Macropus fuliginosus fuliginosus, M. f. melanops and M. f. ocydromus

1982 ◽  
Vol 9 (2) ◽  
pp. 203 ◽  
Author(s):  
WE Poole ◽  
SM Carpenter ◽  
JT Wood
Keyword(s):  
Growth Curve ◽  
Young Animal ◽  
Age Determination ◽  
Growth Curves ◽  
Birth Date ◽  
First Year ◽  
Body Measurements ◽  
Grey Kangaroo ◽  
Pass Through

Seven body measurements were taken at regular intervals throughout life from both male and female western grey kangaroos of known birth date. For each sex of three subspecies and for each body measurement a growth curve was fitted, and confidence intervals calculated for determining the age of new animals. As with eastern grey kangaroos, a phase change in the growth curve was apparent at the time when the young vacate the pouch. Join points in the curve for each subspecies of western grey kangaroos were estimated empirically, as three-quarters through the interval between first emergence and final vacation of the pouch by a young animal. The growth curves were represented by a four-parameter non-linear model consisting of two hyperbolas constrained to pass through the common point. Tables presented contrast the ages at which percentile growth values are attained for each subspecies, and also provide examples of the determination of age from body measurements for both males and females, at monthly intervals during their first year. As found for the eastern grey kangaroo, head length proved to be the most reliable criterion, and all measurements of animals older than 2 years were unreliable for age determination.

Endoparasites of an insular subspecies of the western grey kangaroo, Macropus fuliginosus

2004 ◽  
Vol 52 (6) ◽  
pp. 623 ◽  
Author(s):  
L. S. Webley ◽  
I. Beveridge ◽  
G. Coulson
Keyword(s):  
Parasite Species ◽  
South Australia ◽  
Parasite Prevalence ◽  
Bimodal Distribution ◽  
Tammar Wallaby ◽  
Gastrointestinal Parasites ◽  
Original Population ◽  
Core Species ◽  
Grey Kangaroo ◽  
Western Grey Kangaroo

This study examined parasites occurring in the insular subspecies of the western grey kangaroo, Macropus fuliginosus fuliginosus, from Kangaroo Island. A total of 25 kangaroos from three sites were examined for gastrointestinal parasites. Fifteen parasite species were identified: eight in the stomach, five in the small intestine and two in the large intestine. Parasite prevalence showed a bimodal distribution: 'satellite' species were predominantly cestodes, whereas 'core' species were nematodes. There was no evidence of co-speciation in the 12 parasite species occurring in both island and mainland western grey kangaroo subspecies. M. f. fuliginosus harboured fewer parasite species than M. f. melanops from the Fleurieu Peninsula, South Australia. This might be related to parasite prevalence and the intensity of infection in the original population of kangaroos. Alternatively, it might be related to differing environmental conditions or to chance. Host switching was evident, with Cloacina kartana, which has been recorded as a common parasite of the tammar wallaby, Macropus eugenii, also occurring in some kangaroos.

scholarly journals Defence Is a Priority in Female Juveniles and Adults of Taxus baccata L.

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 844
Author(s):  
Kinga Nowak ◽  
Marian J. Giertych ◽  
Emilia Pers-Kamczyc ◽  
Peter A. Thomas ◽  
Grzegorz Iszkuło
Keyword(s):  
Starch Content ◽  
Pollen Grains ◽  
Pot Experiment ◽  
Total Phenolic ◽  
First Year ◽  
Specific Response ◽  
Taxus Baccata ◽  
Dioecious Plants ◽  
A Priority ◽  
Sexually Mature

Female individuals of dioecious plants invest their resources more in storage and defence, and the males have higher nitrogen content invested in the production of pollen grains. An unresolved problem is whether this strategy occurs only in sexually mature plants or can also occur in juvenile plants. To answer this, Taxus baccata (L.) needles from the mature plants and rooted cuttings (juveniles) in a pot experiment were compared for the content of carbon, nitrogen, starch, total non-structural carbohydrates (TNC), and total phenolic compounds (TPhC). The results indicate that the differences between sexes occurred mainly in sexually mature plants, where the starch content was higher in females and nitrogen in males. However, the novelty of the results is that TPhC was generally higher in females than males in both adults and juveniles, suggesting that defence is a priority for females from an early age. We do not know if this is an innate trait because the strobili production (albeit at a very low level) of juveniles was observed in all individuals after the autumn of the first year. We found no effect of fertilization on sex-specific response in the pot experiment, which may be related to the lower reproductive effort of juveniles.

scholarly journals Age and growth of franciscana dolphins, Pontoporia blainvillei (Cetacea: Pontoporiidae) incidentally caught off southern Brazil and northern Argentina

2010 ◽  
Vol 90 (8) ◽  
pp. 1493-1500 ◽  
Author(s):  
Silvina Botta ◽  
Eduardo R. Secchi ◽  
Mônica M.C. Muelbert ◽  
Daniel Danilewicz ◽  
Maria Fernanda Negri ◽  
...  
Keyword(s):  
Growth Models ◽  
Growth Curves ◽  
Small Sample ◽  
Age And Growth ◽  
Buenos Aires Province ◽  
Von Bertalanffy ◽  
Southern Brazil ◽  
Data Set ◽  
Males And Females ◽  
Pontoporia Blainvillei

Age and length data of 291 franciscana dolphins (Pontoporia blainvillei) incidentally captured on the coast of Rio Grande do Sul State (RS), southern Brazil, were used to fit growth curves using Gompertz and Von Bertalanffy growth models. A small sample of franciscanas (N = 35) from Buenos Aires Province (BA), Argentina, were used to see if there are apparent growth differences between the populations. Male and female franciscana samples from both areas were primarily (78–85%) <4 years of age. The Von Bertalanffy growth model with a data set that excluded animals <1 year of age provided the best fit to data. Based on this model, dolphins from the RS population reached asymptotic length at 136.0 cm and 158.4 cm, for males and females, respectively. No remarkable differences were observed in the growth trajectories of males and females between the RS and BA populations.

Effect of selenium supplementation on survival, liveweight and wool weight of young sheep on Kangaroo Island, South Australia

1979 ◽  
Vol 19 (101) ◽  
pp. 689 ◽  
Author(s):  
SK Walker ◽  
GP Hall ◽  
DH Smith ◽  
RW Ponzoni ◽  
GJ Judson
Keyword(s):  
Total Dose ◽  
Whole Blood ◽  
Sodium Selenite ◽  
South Australia ◽  
Selenium Concentration ◽  
Mortality Rates ◽  
Selenium Supplementation ◽  
First Year ◽  
Weaning Weight ◽  
Fleece Weight

The responses in liveweight, wool weight and survival, to selenium supplementation, were studied in young sheep from weaning to yearling age. The experiment was conducted over three years. In the first year, one sodium selenite supplementation rate was used (total dose 46.5 mg). During the following two years two supplementation rates were administered (total doses 46.5 mg and 93 mg). Mean concentrations of selenium in whole blood in unsupplemented sheep varied from 0.19-0.56 pmol l-l and from 0.20-0.44 pmol l-1 in the two years in which concentrations were measured. Supplementation, which commenced at lamb marking, increased the selenium concentration in sheep at weaning and thereafter. Selenium supplementation improved the break-of-season weight (P < 0.01) and yearling weight (P < 0.01 ) but not weaning weight (0.05 < P < 0.1 ). Hogget fleece weight was improved (P < 0.01 ) and mortality reduced (P < 0.01) by selenium supplementation. There was a treatment x year interaction in mortality rates (P < 0.01 ). There were no significant differences between the two supplementation rates

Sign in / Sign up

Export Citation Format

Share Document