A 10-year demographic study of a small mammal community in the Australian Alps

2015 ◽  
Vol 63 (5) ◽  
pp. 338 ◽  
Author(s):  
D. C. D. Happold
Keyword(s):  
Small Mammals ◽  
Life Histories ◽  
High Fecundity ◽  
Annual Variations ◽  
Subalpine Zone ◽  
Australian Alps ◽  
Small Mammal Community ◽  
Rattus Fuscipes ◽  
Interannual Fluctuations ◽  
Population Numbers

This paper describes a 10-year study of the community of two species of small rodents (Mastacomys fuscus, Rattus fuscipes) and one species of dasyurid marsupial (Antechinus swainsonii) in the subalpine zone of the Australian Alps. Each species exhibited differing life-histories with respect to population numbers, intra- and interannual fluctuations in numbers, reproduction, proportion of young in the population, winter survival, immigration and longevity. Of the two species of rodents, M. fuscus had the lowest population numbers, was the least fecund, had the highest rate of survival, and the smallest fluctuations in numbers. A. swainsonii was the least numerous species, and the winter die-off of males and the high fecundity of females resulted in much greater fluctuations in numbers than for either rodent. For all species, there were interannual variations in most demographic parameters, suggesting considerable flexibility in response to annual variations in the environment. None of the three species is known to hibernate, nor is there any evidence of cyclicity, as shown by some species of subarctic and arctic small mammals. Comparisons are made with subalpine small mammals in other parts of the world and the influence of the subalpine environment in determining population numbers is considered.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby
Keyword(s):  
Small Mammals ◽  
New South ◽  
New South Wales ◽  
Canopy Cover ◽  
Ground Cover ◽  
First Year ◽  
Severe Effect ◽  
South Wales ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.

Changes in small mammal communities after logging in north-central Ontario

1983 ◽  
Vol 61 (5) ◽  
pp. 970-980 ◽  
Author(s):  
Arthur M. Martell
Keyword(s):  
Small Mammals ◽  
Small Mammal ◽  
Vegetative Cover ◽  
North Central ◽  
Clear Cut ◽  
Clear Cutting ◽  
Small Mammal Community ◽  
Small Mammal Communities ◽  
Mammal Community ◽  
Mammal Communities

Changes in small mammal communities following logging were monitored in clear-cut and strip-cut upland black spruce (Picea mariana) stands and in selectively cut mixed wood stands in north-central Ontario. Clear-cutting and subsequent scarification essentially eliminated the vegetative cover. Much of the ground cover recovered within 5 years and shrubs within 12 years, but mosses and lichens took much longer. The small mammal community in both clear-cut and strip-cut stands changed over the first three years after logging from one dominated by southern red-backed voles (Clethrionomys gapperi) to one dominated by deer mice (Peromyscus maniculatus) and then remained relatively stable for up to 13 years after harvest. That shift was not apparent in selectively cut mixed wood stands where the composition of the small mammal community was similar between uncut stands and stands 4–23 years after harvest. There was relatively little change in total numbers of small mammals after logging. In general, the diversity and evenness of small mammals increased or remained stable in the first 1–3 years following harvest, decreased on older (3–16 years) cuts, and then increased to values similar to those in uncut stands on the oldest (19–23 years) cuts.

scholarly journals The effects of population synchrony, life history, and access constraints on benefits from fishing portfolios

2020 ◽  
Author(s):  
Kiva L. Oken ◽  
André E Punt ◽  
Daniel S. Holland
Keyword(s):  
Environmental Conditions ◽  
Life Histories ◽  
Oncorhynchus Tshawytscha ◽  
Environmental Drivers ◽  
Management Options ◽  
Population Synchrony ◽  
Natural Systems ◽  
Advantages And Disadvantages ◽  
Interannual Fluctuations ◽  
Short Time

Natural resources often exhibit large interannual fluctuations in productivity driven by shifting environmental conditions, and this translates to high variability in the revenue resource users can earn. However, users can dampen this variability by harvesting a portfolio of resources. In the context of fisheries, this means targeting multiple populations, though the ability to actually build diverse fishing portfolios is often constrained by the costs and availability of fishing permits. These constraints are generally intended to prevent overcapitalization of the fleet and ensure populations are fished sustainably. As linked human-natural systems, both ecological and fishing dynamics influence the specific advantages and disadvantages of increasing the diversity of fishing portfolios. Specifically, a portfolio of synchronous populations with similar responses to environmental drivers should reduce revenue variability less than a portfolio of asynchronous populations with opposite responses. We built a bioeconomic model characterized by the Dungeness crab (Metacarcinus magister), Chinook salmon (Oncorhynchus tshawytscha), and groundfish fisheries in the California Current, and used it to explore the influence of population synchrony and permit access on revenue patterns. As expected, synchronous populations reduced revenue variability less than asynchronous populations, but only for portfolios including crab and salmon. Synchrony with longer-lived groundfish populations was not important because environmentally-driven changes in groundfish early life survival were mediated by growth and natural mortality over the full population age structure, and overall biomass was relatively stable across years. Thus, building a portfolio of diverse life histories can buffer against the impacts of extremely poor environmental conditions over short time scales, though not for long-term declines. Increasing access to all permits generally led to increased revenue stability and decreased inequality of the fleet, but also resulted in less revenue earned by an individual from a given portfolio because more vessels shared the available biomass. This means managers are faced with a tradeoff between the average revenue individuals earn and the risk those individuals accept. These results illustrate the importance of considering connections between social and ecological dynamics when evaluating management options that constrain or facilitate fishers’ ability to diversify their fishing.

Small-scale temporal and spatial variation in Atlantic cod (Gadus morhua) life history

2003 ◽  
Vol 60 (9) ◽  
pp. 1111-1121 ◽  
Author(s):  
Tara M McIntyre ◽  
Jeffrey A Hutchings
Keyword(s):  
Body Mass ◽  
Life Histories ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Spatial Scales ◽  
Gonadosomatic Index ◽  
Small Scale ◽  
Hepatosomatic Index ◽  
Georges Bank ◽  
High Fecundity

Life histories of Atlantic cod (Gadus morhua) from the Gulf of St. Lawrence south to Georges Bank differ significantly through time and space. Within the Southern Gulf, fecundity per unit body mass differed by more than 40% over short (2 years) and long (42–45 years) periods of time. Significant variation in size-specific fecundity is also evident among populations: Southern Gulf cod produce almost 30% more eggs per unit body mass than those on Georges Bank, whereas fecundity of Scotian Shelf cod is almost half that of cod in Sydney Bight. Compared with those on Georges Bank, Southern Gulf cod life histories are characterized by high fecundity, late maturity, high gonadosomatic index, and large eggs. Relative to the influence of body size, neither temporal nor spatial differences in fecundity can be attributed to physiological condition, as reflected by liver weight, hepatosomatic index, and Fulton's K. Delayed maturity and higher reproductive allotment among Southern Gulf cod can be explained as selection responses to slower growth, higher prereproductive mortality, and fewer lifetime reproductive events. Patterns of covariation in heritable, fitness-related traits suggest the existence of adaptive variation and evolutionarily significant units at spatial scales considerably smaller than the species range in the Northwest Atlantic.

scholarly journals Tick-Borne Encephalitis Virus: Seasonal and Annual Variation of Epidemiological Parameters Related to Nymph-to-Larva Transmission and Exposure of Small Mammals

Pathogens ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 518
Author(s):  
Laure Bournez ◽  
Gerald Umhang ◽  
Marie Moinet ◽  
Céline Richomme ◽  
Jean-Michel Demerson ◽  
...  
Keyword(s):  
Small Mammals ◽  
Temporal Variations ◽  
Encephalitis Virus ◽  
Myodes Glareolus ◽  
Mountain Forest ◽  
Annual Variations ◽  
Tick Borne Encephalitis ◽  
Tick Borne Encephalitis Virus ◽  
Over Time ◽  
Epidemiological Parameters

A greater knowledge of the ecology of the natural foci of tick-borne encephalitis virus (TBEV) is essential to better assess the temporal variations of the risk of tick-borne encephalitis for humans. To describe the seasonal and inter-annual variations of the TBEV-cycle and the epidemiological parameters related to TBEV nymph-to-larva transmission, exposure of small mammals to TBEV, and tick aggregation on small mammals, a longitudinal survey in ticks and small mammals was conducted over a 3-year period in a mountain forest in Alsace, eastern France. TBEV prevalence in questing nymphs was lower in 2013 than in 2012 and 2014, probably because small mammals (Myodes glareolus and Apodemus flavicollis) were more abundant in 2012, which reduced tick aggregation and co-feeding transmission between ticks. The prevalence of TBEV in questing nymphs was higher in autumn than spring. Despite these variations in prevalence, the density of infected questing nymphs was constant over time, leading to a constant risk for humans. The seroprevalence of small mammals was also constant over time, although the proportion of rodents infested with ticks varied between years and seasons. Our results draw attention to the importance of considering the complex relationship between small mammal densities, tick aggregation on small mammals, density of infected questing nymphs, and prevalence of infected nymphs in order to forecast the risk of TBEV for humans.

The short-term responses of small mammals to wildfire in semiarid mallee shrubland, Australia

2010 ◽  
Vol 37 (4) ◽  
pp. 293 ◽  
Author(s):  
Luke T. Kelly ◽  
Dale G. Nimmo ◽  
Lisa M. Spence-Bailey ◽  
Michael F. Clarke ◽  
Andrew F. Bennett
Keyword(s):  
Life History ◽  
Small Mammals ◽  
Small Mammal ◽  
Vegetation Structure ◽  
Large Scale ◽  
Response Patterns ◽  
Before And After ◽  
Resource Requirements ◽  
Small Mammal Community ◽  
And Function

Context. Wildfire is a major driver of the structure and function of mallee eucalypt- and spinifex-dominated landscapes. Understanding how fire influences the distribution of biota in these fire-prone environments is essential for effective ecological and conservation-based management. Aims. We aimed to (1) determine the effects of an extensive wildfire (118 000 ha) on a small mammal community in the mallee shrublands of semiarid Australia and (2) assess the hypothesis that the fire-response patterns of small mammals can be predicted by their life-history characteristics. Methods. Small-mammal surveys were undertaken concurrently at 26 sites: once before the fire and on four occasions following the fire (including 14 sites that remained unburnt). We documented changes in small-mammal occurrence before and after the fire, and compared burnt and unburnt sites. In addition, key components of vegetation structure were assessed at each site. Key results. Wildfire had a strong influence on vegetation structure and on the occurrence of small mammals. The mallee ningaui, Ningaui yvonneae, a dasyurid marsupial, showed a marked decline in the immediate post-fire environment, corresponding with a reduction in hummock-grass cover in recently burnt vegetation. Species richness of native small mammals was positively associated with unburnt vegetation, although some species showed no clear response to wildfire. Conclusions. Our results are consistent with the contention that mammal responses to fire are associated with their known life-history traits. The species most strongly affected by wildfire, N. yvonneae, has the most specific habitat requirements and restricted life history of the small mammals in the study area. The only species positively associated with recently burnt vegetation, the introduced house mouse, Mus domesticus, has a flexible life history and non-specialised resource requirements. Implications. Maintaining sources for recolonisation after large-scale wildfires will be vital to the conservation of native small mammals in mallee ecosystems.

The Response of Small Mammals to Clearing and Burning of Eucalypt Forest in South-eastern Australia

1979 ◽  
Vol 6 (2) ◽  
pp. 151 ◽  
Author(s):  
GR Friend
Keyword(s):  
Small Mammals ◽  
Native Species ◽  
Early Summer ◽  
Native Forest ◽  
Pine Plantation ◽  
Eucalypt Forest ◽  
Population Turnover ◽  
Eastern Australia ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

Before, during and after a clearing operation for pine plantation establishment, small mammals were trapped on ridges which were to be cleared of all vegetation, and in adjacent gullies which were to be permanently retained under native forest. Rattus fuscipes was the most abundant native species on all grids throughout the study, while R. lutreolus, Antechinus stuartii and A. swainsonii were in low abundance. Clearing in early summer, the breeding season in most of these species, resulted in an acceleration and accentuation of population turnover. Some juveniles and subadults may have moved from the ridges during clearing, while breeding adults remained and probably perished. Populations of R. fuscipes on ridge areas were drastically reduced by clearing and windrowing, but subadults recolonized the affected areas within 1-2 months. Results for the other three native species were inconclusive, due to the few individuals captured at any time during the study. The exotic species Mus musculus began to invade immediately following windrow burning.

scholarly journals Small terrestrial mammal distributions in Simien Mountains National Park, Ethiopia: a reassessment after 88 years

2020 ◽  
Vol 101 (3) ◽  
pp. 634-647 ◽  
Author(s):  
Evan W Craig ◽  
William T Stanley ◽  
Julian C Kerbis Peterhans ◽  
Josef Bryja ◽  
Yonas Meheretu
Keyword(s):  
Climate Change ◽  
Small Mammals ◽  
National Park ◽  
Natural Habitat ◽  
General Pattern ◽  
Western Slope ◽  
Northern Ethiopia ◽  
Data Set ◽  
Small Mammal Community ◽  
Distribution And Ecology

Abstract Despite the presence of mostly endemic species, the most comprehensive data set on the distribution and ecology of small mammals inhabiting Simien Mountains National Park (SMNP) dated from 1927. The study we carried out and report here provides a unique opportunity to assess the possible role of climate change over the last 88 years on the elevational distribution of mammals in the Ethiopian highlands. Between September and November 2015, three of us (EWC, WTS, YM) collected nonvolant small mammals at four sites (2,900, 3,250, 3,600, and 4,000 m a.s.l.) along the western slope of the Simien Mountains using standardized sampling. Over a 4-week period we recorded 13 species, comprising 11 species of rodents and two of shrews, all endemic to the Ethiopian Plateau. We found the greatest species richness at mid-elevations (3,250 m), consistent with a general pattern found on many other mountains worldwide, but less so in Africa. We compared our species distribution results to the 1927 data set and found upward elevational shifts in species’ ranges, highlighting the role and influence of climate change on the small mammal community. SMNP represents an exceptionally valuable core area of endemism and the best protected natural habitat in northern Ethiopia.

scholarly journals Present-day African analogue of a pre-European Amazonian floodplain fishery shows convergence in cultural niche construction

2016 ◽  
Vol 113 (52) ◽  
pp. 14938-14943 ◽  
Author(s):  
Doyle B. McKey ◽  
Mélisse Durécu ◽  
Marc Pouilly ◽  
Philippe Béarez ◽  
Alex Ovando ◽  
...  
Keyword(s):  
Life Histories ◽  
Niche Construction ◽  
Dry Season ◽  
South American ◽  
High Fecundity ◽  
Large Numbers ◽  
Sustainable Fishery ◽  
Reproductive Cycles ◽  
Cultural Niche ◽  
Cultural Niche Construction

Erickson [Erickson CL (2000)Nature408 (6809):190–193] interpreted features in seasonal floodplains in Bolivia’s Beni savannas as vestiges of pre-European earthen fish weirs, postulating that they supported a productive, sustainable fishery that warranted cooperation in the construction and maintenance of perennial structures. His inferences were bold, because no close ethnographic analogues were known. A similar present-day Zambian fishery, documented here, appears strikingly convergent. The Zambian fishery supports Erickson’s key inferences about the pre-European fishery: It allows sustained high harvest levels; weir construction and operation require cooperation; and weirs are inherited across generations. However, our comparison suggests that the pre-European system may not have entailed intensive management, as Erickson postulated. The Zambian fishery’s sustainability is based on exploiting an assemblage dominated by species with life histories combining high fecundity, multiple reproductive cycles, and seasonal use of floodplains. As water rises, adults migrate from permanent watercourses into floodplains, through gaps in weirs, to feed and spawn. Juveniles grow and then migrate back to dry-season refuges as water falls. At that moment fishermen set traps in the gaps, harvesting large numbers of fish, mostly juveniles. In nature, most juveniles die during the first dry season, so that their harvest just before migration has limited impact on future populations, facilitating sustainability and the adoption of a fishery based on inherited perennial structures. South American floodplain fishes with similar life histories were the likely targets of the pre-European fishery. Convergence in floodplain fish strategies in these two regions in turn drove convergence in cultural niche construction.

Sign in / Sign up

Export Citation Format

Share Document