scholarly journals Response of a remnant marmot population to habitat enhancement yields insights into marmot ecology

2020 ◽  
Vol 101 (3) ◽  
pp. 658-669
Author(s):  
Melissa J Reynolds-Hogland ◽  
Alan B Ramsey ◽  
August T Seward ◽  
Kristine L Pilgrim ◽  
Cory Engkjer ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Young Population ◽  
Marmota Flaviventris ◽  
Livestock Management ◽  
Adult Females ◽  
Capture Recapture ◽  
Geographic Expansion ◽  
Age Structured ◽  
Habitat Enhancement ◽  
Remnant Population

Abstract We evaluated the response of a remnant population of yellow-bellied marmots (Marmota flaviventris) to targeted habitat enhancement in an ecological system that had been degraded during ~100 years of intensive livestock management, including marmot eradication. We used capture-recapture data and a novel use of a multistate framework to evaluate geographic expansion of the marmot population pre- and post-habitat enhancement. We also estimated age-structured survival, reproduction, and sex ratios. The marmot population appeared to respond positively to new habitat opportunities created by habitat enhancement: the number of marmots captured increased from three marmots pre-habitat enhancement to 54 (28 adults and yearlings, 26 young) post-habitat enhancement at the end of the study. Marmots expanded geographically by transitioning into habitat-enhanced areas, and adult females occupied and reproduced in all habitat-enhanced areas. The sex ratio of the young population in 2019 was strongly female-biased, which may have been influenced by poor body condition of breeding females owing to unusually prolonged snow cover that year. Adult and yearling survival were within the range of that reported for colonial adults and yearlings in Colorado. Our results suggest that active habitat enhancement can assist in the recovery of marmot populations in systems where marmots historically existed.

The eastern horseshoe bat, Rhinolophus megaphyllus, in south-east Queensland, Australia: colony demography and dynamics, activity levels, seasonal weight changes, and capture-recapture analyses

2001 ◽  
Vol 28 (4) ◽  
pp. 425 ◽  
Author(s):  
R. A. Young
Keyword(s):  
Population Size ◽  
Colony Size ◽  
Activity Levels ◽  
Adult Males ◽  
Weight Changes ◽  
Adult Females ◽  
Colony Demography ◽  
Capture Recapture ◽  
Horseshoe Bat ◽  
Size Estimates

During this study, 634 eastern hoseshoe bats, Rhinolophus megaphyllus, were captured at three colonies in south-east Queensland, with most data coming from two colonies (Anjuramba mine and Ravensbourne cave). Colony size, sex ratios, age structure, and colony function varied between colonies and with season. Capture–recapture data of banded bats was used to monitor movement patterns, seasonal weight changes, colony-size estimates at Anjuramba (JOLLY model), and the recapture frequency according to sex and age. The JOLLY estimator of the population size over-estimated the actual population at Anjuramba on most occasions but paralleled changes in population size. Of the 319 bats banded, 21.9% were recaptured, with only one recovery involving a movement between roosts. Adult males have a high roost-site fidelity and are more sedentary than adult females. The recapture rate and recapture frequency for adult males was significantly higher than for adult females. R. megaphyllus is active throughout the year but may enter torpor for short periods, with more females than males observed in torpor. There was no significant association between torpor and season. Longevity records of 7 years and 1 month were recorded for a sub-adult female and 7 years and 7 months for a juvenile female.

scholarly journals Description and Biological Studies of a New Species of Metaphycus Mercet, 1917 (Hymenoptera: Encyrtidae), A Parasitoid of Capulinia linarosae Kondo & Gullan

2019 ◽  
Vol 11 ◽  
pp. 117954331985796
Author(s):  
Dorys T Chirinos ◽  
Takumasa Kondo
Keyword(s):  
Sex Ratio ◽  
Insect Pest ◽  
Morphological Characteristics ◽  
Psidium Guajava ◽  
Adult Longevity ◽  
Single Male ◽  
Adult Females ◽  
Biological Studies ◽  
Control Programmes ◽  
Baseline Information

The guava cottony scale, Capulinia linarosae Kondo & Gullan (Hemiptera: Eriococcidae), is an important pest of guava, Psidium guajava L. (Myrtaceae) in northern Colombia and Venezuela. A species of Metaphycus (Hymenoptera: Encyrtidae) is the only known primary parasitoid associated with this insect pest. The parasitoid is herein described as M. marensis Chirinos & Kondo, sp. nov., based on morphological characteristics of the adult female and male. Biological studies on adult longevity, fecundity, host preference, and sex ratio were conducted. The maximum longevity of the female and the male were 8.0 and 6.5 days, respectively, when fed with diluted honey. On average, a fed mated female laid approximately 40 eggs. Adult females of M. marensis were shown to prefer to parasitize 11- to 15-day-old adult females of C. linarosae and do not parasitize first-instar nymphs of the host eriococcid. The female-to-male sex ratio of the parasitoid was 2.24: 1. When ovipositing females of M. marensis were given only small-sized individuals (second-instar nymphs) of C. linarosae, generally the resulting progeny was a single male wasp. This parasitoid species has arrhenotokous reproduction and is a facultative gregarious parasitoid. These results show a short adult longevity, as well as a relatively low fecundity of the female compared with studies conducted on other Metaphycus species. This study provides essential baseline information for future biological control programmes for C. linarosae.

Studies on the behaviour on the South Ausralian fur seal, Arctocephalus forsteri (Lesson) II. Adult females and pups

1971 ◽  
Vol 19 (3) ◽  
pp. 267 ◽  
Author(s):  
I Stirling
Keyword(s):  
Sex Ratio ◽  
Breeding Season ◽  
Male And Female ◽  
Specific Location ◽  
Adult Females ◽  
Specific Behaviour ◽  
Fur Seal ◽  
O 47 ◽  
High Degree ◽  
Regular Patterns

A. forsteri pups were all weaned by 1 year old and were then totally absent from the island during the breeding season. The recorded intervals, for three tagged females, between apparent weaning of one pup and birth of the next were 29, 40, and 60 days. Some females became infested with barnacles during the period of feeding at sea prior to parturition. Adult females showed a high degree of fidelity to specific breeding colonies. Little specific behaviour, other than restlessness, preceded birth. Five observed births took from 5 sec to 4 min. Pups could swim when born. Male and female newborn pups weighed 4.41 =0.60 and 4.11 +O.47 kg respectively; the sex ratio was not significantly different from unity. Pups stayed with their mothers at a specific location for the first few days, after which the females began to feed at sea and the pups began to associate with each other. Females had not established regular patterns of presence and absence in the pupping colony by early February, but did so by late April. Females did not defend even newborn pups from approaching humans.

BIONOMICS OF ENOCLERUS BARRI (COLEOPTERA: CLERIDAE)

1969 ◽  
Vol 101 (4) ◽  
pp. 382-386 ◽  
Author(s):  
Richard E. Rice
Keyword(s):  
British Columbia ◽  
Life Cycle ◽  
North America ◽  
Sex Ratio ◽  
Rocky Mountain ◽  
Mountain Region ◽  
Western North America ◽  
Adult Females ◽  
Rocky Mountain Region ◽  
Life Cycle Stages

AbstractEnoclerus barri Knull occurs in western North America from British Columbia south to Mexico and throughout the Rocky Mountain region. Adults were collected at Grass Valley, Calif., from May to September at traps baited with beetle attractants. Collections occurred at temperatures ranging from 22.5° to 31 °C; the sex ratio of trapped beetles was 4.5 females to 1 male. Duration of life cycle stages at 24 ± 2 °C were: egg, 9 days; larva, first iastar, 14 days; second instar, 12 days; third instar feeding stage, 14 days. All larvae reared to third instar failed to pupate in the laboratory. Adult females of unknown age when collected lived from 10 to 131 days and produced an average of 389 eggs per female. Enoclerus barri utilized six species of Scolytidae as hosts in the laboratory.

Distribution and Demographic Attributes of Platypus Populations Near Melbourne.

1998 ◽  
Vol 20 (2) ◽  
pp. 313
Author(s):  
M. Serena ◽  
G.A. Williams
Keyword(s):  
Population Density ◽  
Sex Ratio ◽  
River Catchment ◽  
Good Physical Condition ◽  
Adult Females ◽  
Release Studies ◽  
Index 2 ◽  
Demographic Attributes ◽  
Fyke Nets ◽  
Yarra River

Information on platypus populations occurring along streams in the Melbourne region was collected by mark- release studies in the period I989-I996. In all, 256 records of animals were obtained along waterways in the Yarra River, Maribyrnong River and Dandenong Creek catchments. Ornilhorhynchus anatinus were captured at approximately one-quarter of the sites sampled by fyke nets, with animals encountered to within about 15 km of inner Melbourne. Evidence of reproduction was obtained along seven waterways in the Yarra River catchment (Badger Creek, Watts River/Graceburn Creek, Olinda Creek, Mullum Mullum Creek, Diamond Creek, Plenty River/Jacks Creek and the Yarra River itself) as well as Monbulk Creek in the Oandenong Creek catchment. The earliest date on which a juvenile was captured at any site was 24 February. Across populations, sex ratio (expressed as the number of adult or subadult females per adult male) tended to be positively correlated with population density. In all seasons, nearly all animals were found to be in moderate to good physical condition (i.e. tail fat index = 2 or 3). The three thinnest individuals encountered in this study were adult females captured in March, at least two of which were lactating. Along the Watts River and Mullum Mullum Creek, six individuals (comprising about 10% of animals captured) had one or more pieces of plastic or rubber litter caught around their neck or thorax.

Blackbuck Antilope cervicapra (Mammalia: Cetartiodactyla: Bovidae) estimates in human-dominated landscape in Aligarh, Uttar Pradesh, India

2021 ◽  
Vol 13 (9) ◽  
pp. 19232-19238
Author(s):  
Mujahid Ahamad ◽  
Jamal A. Khan ◽  
Satish Kumar
Keyword(s):  
Sex Ratio ◽  
Uttar Pradesh ◽  
Adult Males ◽  
Forest Patches ◽  
Female Ratio ◽  
Adult Females ◽  
Or Groups ◽  
Feral Dogs ◽  
The Status ◽  
Antilope Cervicapra

Information on the status of the Indian Blackbuck Antilope cervicapra is mostly available from protected areas (PA), although 80% of its population occurs outside PAs. We conducted surveys to assess the status, age structure, sex ratio, and conservation issues of Blackbuck in and around Aligarh between February and June 2014. A median of 672 individuals at 18 separate locations were recorded with a group size ranging 4–216 except for solitary individuals. The abundance of Blackbuck was maximum in Sikandra Rao (range: 154–216) followed by Andla (range: 47–65), and Pala-Sallu (range: 53–62). Sex ratio was skewed towards females (1:4.5) with yearling to female and fawn to female ratio of 7.8:100 and 6.7:100, respectively. The percentage of adult males of Blackbuck (12.8% adult males, 8.4% sub-adult males) as well as adult females (56.4% adult females, 11.9% sub-adult females) was higher than other age classes or groups in the population. The preliminary observations indicate that the increasing population of free-ranging feral dogs, degradation of forest patches, social forestry plantations, competition with livestock, and poaching pressure are the major conservation issues of Blackbuck in the area. The current information is expected to serve as baseline in assessing the population of Blackbuck in the future. 

Common vole (Microtus arvalis) population sex ratio: biases and process variation

2005 ◽  
Vol 83 (11) ◽  
pp. 1391-1399 ◽  
Author(s):  
Josef Bryja ◽  
Jiřina Nesvadbová ◽  
Marta Heroldová ◽  
Eva Jánová ◽  
Jan Losík ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Process Variation ◽  
Methodological Approach ◽  
Survival Rates ◽  
Common Vole ◽  
Joint Effect ◽  
Microtus Arvalis ◽  
Differential Survival ◽  
Capture Recapture ◽  
Error Bias

Vole population sex ratio varies seasonally. However, population sex ratios have usually been estimated using naïve estimators that do not allow for biases owing to the sex difference in capture probabilities and movement distances (i.e., effective areas sampled). Here we aimed to advance the methodological approach, recognizing that there are two different classes of contributing mechanisms to the pattern which are best addressed separately: (1) those mechan isms imposing a systematic error (bias) in population estimates and (2) those generating the true process variation. Analyzing 7-year capture–recapture data in the common vole (Microtus arvalis (Pallas, 1778)), we quantified both types of biases and revealed that the bias owing to differential capture rates was often severe and less predictable, whereas that owing to differential effective areas was smaller and overestimated male numbers for most of the year. We demonstrated unambiguously that the unbiased population sex ratio indeed varies seasonally, with the males usually being more numerous over winter and spring. By testing predictions from two mechanistic hypotheses to explain the process variability, we found evidence for both the differential recruitment hypothesis and the differential survival hypothesis. From April–May to August, it was the females that were recruited more to the population and that had higher survival rates than males. We suggest that the seasonal variation in the population sex ratio is not merely a result of biasing mechanisms but an important population property driven by the joint effect of differential recruitment and differential survival between sexes.

Some Mechanisms That Affect the Sex Ratio of Nasonia vitripennis (Walk.) (Hymenoptera: Pteromalidae) Reared From Superparasitized Housefly Pupae

1966 ◽  
Vol 98 (6) ◽  
pp. 645-653 ◽  
Author(s):  
H. G. Wylie
Keyword(s):  
Sex Ratio ◽  
Musca Domestica ◽  
Nasonia Vitripennis ◽  
Female Progeny ◽  
Male Progeny ◽  
Adult Females

AbstractFemale Nasonia vitripennis (Walk.) parasitizing housefly (Musca domestica L.) pupae produce a smaller percentage of female progeny at high parasite:host ratios than at lower ones because they fertilize a smaller percentage of their eggs (in this species unfertilized eggs produce male progeny), and because more female than male larvae die on superparasitized hosts. The adult females fertilize relatively fewer eggs at high than at low parasite:host ratios for two reasons. First, they encounter relatively more previously attacked hosts, on which they lay a smaller percentage of fertilized eggs than on previously unattacked ones; second, they more often encounter other female parasites while ovipositing, and this interference reduces the percentage of fertilized eggs they lay.

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