Porcupine (Erethizon dorsatum) demography in central Massachusetts

1996 ◽  
Vol 74 (3) ◽  
pp. 480-484 ◽  
Author(s):  
Mary B. Hale ◽  
Todd K. Fuller
Keyword(s):  
Population Dynamics ◽  
Rate Of Change ◽  
Demographic Parameters ◽  
Adult Males ◽  
Erethizon Dorsatum ◽  
Annual Survival ◽  
Adult Females ◽  
Survival And Reproduction ◽  
Pregnancy Status ◽  
Annual Mortality

From 1991 to 1993 we radio-collared and monitored 50 porcupines (Erethizon dorsatum) in central Massachusetts to obtain estimates of survival and reproduction, and applied these estimates to a model of porcupine population dynamics to estimate the annual rate of change (λ). The annual survival rate for all adult (> 1 year old) porcupines was 0.67 ± 0.07 (mean ± SE). Survival was higher, but not significantly so (P = 0.22), for adult females (0.74 ± 0.08) than for adult males (0.56 ± 0.12). Adult porcupines died of starvation (annual mortality rate 0.08), injuries (0.05), interactions with humans (0.04), and disease (0.05) but not predation. Annual survival of juveniles (< 1 year old) ranged from at least 0.37 in 1992 to at most 0.39 in 1993. Minimum birth rates of radio-collared females > 2 years old, determined by sightings of young near females, lactation, and pregnancy status as determined by ultrasound, were 0.64 in 1992 and 0.62 in 1993. Incorporation of maximum and minimum values of demographic parameters from this study and from the literature into population models indicated a decreasing porcupine population.

Population dynamics of Newfoundland beaver

1977 ◽  
Vol 55 (9) ◽  
pp. 1480-1492 ◽  
Author(s):  
Arthur T. Bergerud ◽  
Donald R. Miller
Keyword(s):  
Population Dynamics ◽  
Mortality Rate ◽  
Litter Size ◽  
Food Resources ◽  
Territorial Behaviour ◽  
Population Densities ◽  
Adult Females ◽  
Annual Mortality

The demography of beaver was studied in Newfoundland from 1956 to 1965. Population densities were low and seldom exceeded one colony per 2.6 km2 (1 mi2). About 80% of the adult females were fertile and the number of young per litter averaged 2.7. The annual mortality rate of beavers was about 30% in southeastern Newfoundland. A more detailed study was made of a population living in a 39-km2 (15-mi2) study area. This population had 20, 23, and 24 active colonies, 1958–1960. In 1961 it declined to 18 colonies. We removed the beavers in 1962. The replacement colonies, resulting initially from ingress, were 7 in 1962, 12 in 1963, 17 in 1964, and 15 in 1965. When the population was high in 1958–1960, the fertility of females was high (78%) but the litter size in 1960 appeared to be less than elsewhere. When the population declined in 1960–1961, productivity declined and some animals may have starved over winter. It was concluded that territorial behaviour spaces colonies, dispersing the population within the limits dictated by the availability of water and food resources. However, such a system did not prevent overutilization of food resources and decline of the population from reduced reproduction and increased mortality.

scholarly journals Variation of glucocorticoid metabolite levels is associated with survival demands in immature and reproductive demands in adult wild black capuchins (Sapajus nigritus)

2016 ◽  
Vol 9 (2) ◽  
pp. 20-29 ◽  
Author(s):  
Caio M. Moreira ◽  
Lucas Peternelli Dos Santos ◽  
Maria Bernardete Cordeiro Sousa ◽  
Patrícia Izar
Keyword(s):  
Allostatic Load ◽  
Annual Variation ◽  
Adult Males ◽  
Cumulative Energy ◽  
Fecal Glucocorticoid Metabolites ◽  
Adult Females ◽  
Animal Survival ◽  
Energy Mobilization ◽  
Food Shortages ◽  
Survival And Reproduction

According to the concept of allostasis and its association with energy mobilization, glucocorticoids (GCs) should parallel cumulative energy expenditure for animal survival and reproduction. Therefore, it is expected that seasonal food shortages might lead to increased levels of GCs. We tested this hypothesis by analyzing the intra-annual variation of fecal glucocorticoid metabolites (GCM) in 14 wild black capuchin monkeys (Sapajus nigritus) living in a social group in the Brazilian Atlantic Forest. We analyzed the association between GCM and social and environmental variables for the three age/sex classes (adult males, adult females and immatures [juveniles and infants]). Decreased fruit intake during the dry season increased the GCM levels of both immatures and adult males. Although fruit shortage influenced the allostasis of adult males, the variation in their GCM levels was more impacted by the breeding season. GCM levels of adult females varied during the late stage of pregnancy. These results suggest fruit consumption as the main source of allostatic load for immature animals, while reproductive costs had greater effect on adults. 

scholarly journals Annual Survival and Recruitment in a Ruby-Throated Hummingbird Population, Excluding the Effect of Transient Individuals

The Condor ◽  
2003 ◽  
Vol 105 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Bill Hilton ◽  
Mark W. Miller
Keyword(s):  
Population Dynamics ◽  
South Carolina ◽  
Natural History ◽  
Rate Of Change ◽  
Standard Errors ◽  
Eastern North America ◽  
Metapopulation Dynamics ◽  
Apparent Survival ◽  
Adult Females ◽  
Point Estimates

Abstract We estimated annual apparent survival, recruitment, and rate of population growth of breeding Ruby-throated Hummingbirds (Archilochus colubris), while controlling for transients, by using 18 years of capture-mark-recapture data collected during 1984–2001 at Hilton Pond Center for Piedmont Natural History near York, South Carolina. Resident males had lower apparent survival (0.30 ± 0.05 SE) than females (0.43 ± 0.04). Estimates of apparent survival did not differ by age. Point estimates suggested that newly banded males were less likely than females to be residents, but standard errors of these estimates overlapped (males: 0.60 ± 0.14 SE; females: 0.67 ± 0.09). Estimated female recruitment was 0.60 ± 0.06 SE, meaning that 60% of adult females present in any given year had entered the population during the previous year. Our estimate for rate of change indicated the population of female hummingbirds was stable during the study period (1.04 ± 0.04 SE). We suggest an annual goal of ≥64 adult females and ≥64 immature females released per banding area to enable rigorous future tests for effects of covariates on population dynamics. Development of a broader cooperating network of hummingbird banders in eastern North America could allow tests for regional or metapopulation dynamics in this species. Sobrevivencia Anual y Reclutamiento en una Población del Picaflor Archilochus colubris Excluyendo el Efecto de Individuos Ocasionales Resumen. Estimamos la sobrevivencia anual aparente, reclutamiento y tasa de crecimiento en una población reproductiva del picaflor Archilochus colubris, controlando por la presencia de individuos ocasionales. Utilizamos datos de 18 años de captura-marcaje-recaptura colectados entre 1984 y 2001 en Hilton Pond Center for Piedmont Natural History en cercanías de York, Carolina del Sur. Los machos residentes presentaron una sobrevivencia aparente menor (0.30 ± 0.05 EE) que las hembras (0.43 ± 0.04). Las estimaciones de la sobreviviencia aparente no difirieron entre edades. Estimaciones puntuales sugirieron que los machos marcados por primera vez tuvieron una menor probabilidad de ser residentes que las hembras, pero los errores estándar de estas estimaciones se sobrepusieron (machos: 0.60 ± 0.14 EE; hembras: 0.67 ± 0.09 EE). Para las hembras el reclutamiento estimado fue 0.60 ± 0.06 EE, lo que significa que el 60% de las hembras adultas presentes en un año determinado entraron a la población durante el año anterior. Nuestra estimación de la tasa de cambio indicó que la población de picaflores hembra fue estable durante el período de estudio (1.04 ± 0.02 EE). Para permitir futuras pruebas rigurosas sobre las covariables asociadas a las dinámicas poblacionales, sugerimos una meta anual de ≥64 hembras adultas y ≥64 hembras inmaduras liberadas por área de anillado. La creación de una amplia red cooperativa de anilladores de picaflores en el este de Norteamérica podría permitir estudiar y entender mejor las dinámicas regionales o metapoblacionales de esta especie.

Demography of an introduced population of white-tailed ptarmigan

1983 ◽  
Vol 61 (8) ◽  
pp. 1758-1764 ◽  
Author(s):  
Richard W. Hoffman ◽  
Kenneth M. Giesen
Keyword(s):  
Breeding Habitat ◽  
Adult Males ◽  
Slow Process ◽  
Annual Survival ◽  
Lagopus Leucurus ◽  
Adult Females ◽  
Release Area ◽  
Introduced Population

Forty wild-trapped white-tailed ptarmigan (Lagopus leucurus) were released onto Pike's Peak, Colorado, in June (six mated pairs) and September (9 males, 7 females, 12 juveniles) 1975. Numbers declined 37.5% by the first spring (1976) after the introduction. Spring densities gradually recovered, increasing from 3.4 grouse per 100 ha of breeding habitat in 1976 to 8.4 in 1979, then declined to 7.4 in 1980. Mean distance of territories from the release area increased only 0.86 km (p = 0.44) from 1976 to 1980, reflecting a slow process of expansion. Reproduction was documented in all years including 1975. Survival of released birds until 1976 was 93.3% for males, 46.1% for females, and 33.3% for juveniles. Time of release did not influence survival. Average annual survival (1976–1980) was 64.9% for adult males, 60.3% for adult females, and 43.1% for juveniles. Yearlings comprised 39.7% (range, 20.0 to 54.9%) of all birds (N = 219) identified exclusive of juveniles. Of the 219 birds identified, 137 (62.6%) were males.

Population dynamics of the common wallaroo (Macropus robustus erubescens) in arid New South Wales

1992 ◽  
Vol 19 (1) ◽  
pp. 1 ◽  
Author(s):  
TF Clancy ◽  
DB Croft
Keyword(s):  
Population Dynamics ◽  
New South ◽  
New South Wales ◽  
Density Fluctuations ◽  
Rainfall Regime ◽  
Total Density ◽  
Adult Males ◽  
Adult Females ◽  
South Wales ◽  
The Common

The population dynamics of the common wallaroo or euro (Macropus robustus erubescens) were investigated in two adjacent sites in far western New South Wales. Wallaroo densities were generally higher in a site of high relief (South Ridge) than in one of low relief (South Sandstone); however, both sites exhibited large fluctuations in numbers (ranges of 2.23-18.31 per km*2 and 3.48-19.99 per km*2, respectively). The proportion of adult males relative to adult females was significantly higher in South Sandstone (c. 1.1 : 1) than in South Ridge (c. 0.4: 1), indicating a difference in habitat usage by the sexes. At both sites, fluctuations in overall density were best explained by changes in the density of adult females; however, the relative importance of changes in the numbers of other size-sex classes in determining density fluctuations differed between the two sites. Total density was significantly related to the previous rainfall regime in South Ridge but not in South Sandstone. Reproductive condition of females and survivorship of young were related to environmental conditions. Adult mortality ranged from 4.55 to 25.81% per year and adult survivorship was positively correlated with the abundance of grass. Evidence is presented to support the hypothesis that dispersal of subadults is predominantly a male phenomenon.

scholarly journals Experimenting usage of Camera-traps for Population Dynamics Study of the Asian Elephant Elephas Maximus in Southern India

2007 ◽  
Vol 6 (1) ◽  
pp. 81-95
Author(s):  
Surendra Varma ◽  
André Pittet ◽  
H. S. Jamadagni
Keyword(s):  
Population Dynamics ◽  
Cost Effective ◽  
Camera Trap ◽  
Camera Traps ◽  
Asian Elephant ◽  
Adult Males ◽  
Adult Females ◽  
Juvenile Males ◽  
Long Term Studies

To evaluate the application of camera-trap technology in population dynamics studies of the Asian elephant, indigenously designed, cost-effective, infrared-triggered camera-traps were used.Usability of pictures was defined based on quality, clarity and positioning of the subject.With 99 pictures of 330 elephants, 20 sequences were obtained and 44 distinct individuals were identified.It was found that 38.6% were adult females, 4.5% adult males, 13.6% sub-adult females, 6.8% sub-adult males, 20.4% juvenile females,while juvenile males were poorly represented(2%), and 13.6% were calves.These results were surprising identical with those of other systematic and long-term studies.

Two new species and taxonomic notes on the Neotropical spiny orb-weaving spi-ders Micrathena and Chaetacis (Araneae: Araneidae), with remarks on the development of Micrathena excavata IVAN L. F. MAGALHÃES & ADALBERTO J. SANTOS (Brazil)

Zootaxa ◽  
2011 ◽  
Vol 2983 (1) ◽  
pp. 39 ◽  
Author(s):  
IVAN L. F. MAGALHÃES ◽  
ADALBERTO J. SANTOS
Keyword(s):  
New Species ◽  
Junior Synonym ◽  
Adult Males ◽  
Development Stages ◽  
Brazilian Amazonia ◽  
Central Brazil ◽  
Adult Females ◽  
Two New Species ◽  
Senior Synonym ◽  
First Time

In this paper, M. yanomami n. sp., from Brazilian Amazonia, Chaetacis bandeirante n. sp., from Central Brazil, and the males of M. gaujoni Simon, 1897 and M. ruschii (Mello-Leitão, 1945) n. comb. , respectively from Ecuador and Brazil, are described and illustrated for the first time. An ontogenetic series of the last development stages of both sexes of Micrathena excavata (C. L. Koch, 1836) is illustrated and briefly described. Adult females are larger and have longer legs and larger abdomens than adult males. Probably females undergo at least one additional moult before adulthood, compared to males. Micrathena ornata Mello-Leitão, 1932 is considered a junior synonym of M. plana (C. L. Koch, 1836), and M. mastonota Mello-Leitão 1940 is synonymized with M. horrida (Taczanowski, 1873). Acrosoma ruschii Mello-Leitão, 1945 is revalidated, transferred to Micrathena and considered a senior synonym of M. cicuta Gonzaga & Santos, 2004. Chaetacis necopinata (Chickering, 1960) is recorded for Brazil for the first time. Chaetacis incisa (Walckenaer, 1841) is considered a nomen dubium.

Spacing, movements, and habitat selection of the river otter in boreal Alberta

1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero
Keyword(s):  
Lontra Canadensis ◽  
Home Ranges ◽  
Adult Males ◽  
Movement Rates ◽  
River Otters ◽  
Aquatic Mammal ◽  
Adult Females ◽  
Two Factors ◽  
Bog Lakes ◽  
Selection Of

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.

Time-Budgets of Camargue Horses Ii. Time-Budgets of Adult Horses and Weaned Sub-Adults

Behaviour ◽  
1980 ◽  
Vol 72 (1-2) ◽  
pp. 26-48 ◽  
Author(s):  
Patrick Duncan
Keyword(s):  
Social Structure ◽  
Social System ◽  
General Trend ◽  
Small Population ◽  
Time Budgets ◽  
Adult Males ◽  
Adult Females ◽  
Young Horses

AbstractTime-budgets of adult and weaned sub-adult horses were studied in a small population of Camargue horses living in semi-liberty. The categories of activities used were: Standing resting, Lying flat, Lying up, Standing alert, Walking, Trotting, Galloping, Rolling and Foraging. The main differences in time-budgets were related to age and to sex : young horses spent more time lying (sleeping), males spent more time standing alert and in rapid movements (trot, gallop), while usually foraging less than did the adult females. During the three years of the study the population increased from 20 to 54 horses and there were considerable changes in social structure as the number of adult males increased. Associated with these developments there were some changes between years in the time-budgets: the most striking of which was a general trend for all horses to spend less time lying. Nonetheless the time-budgets showed a considerable constancy across years and age/sex-classes, especially with regard to time spent foraging. This conclusion may provide a clue as to why horses have an unusual social system based on long term relationships between a male and the females of his harem.

Extrinsic Inter- and Intra-specific Competition in Parasitoid Wasps

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Paul J. Ode ◽  
Dhaval K. Vyas ◽  
Jeffrey A. Harvey
Keyword(s):  
Developmental Stages ◽  
Interference Competition ◽  
Apparent Competition ◽  
Annual Review ◽  
Publication Date ◽  
Natural Ecosystem ◽  
Adult Males ◽  
Alternate Host ◽  
Adult Females ◽  
Behavioral Mechanisms

The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host–parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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