scholarly journals Habitat Preferences of Juvenile Abalone (Haliotis mariae Wood, 1828) Along the Dhofar Coast of Oman and Implications for Conservation

2012 ◽  
Vol 17 ◽  
pp. 45 ◽  
Author(s):  
Schalk Willem Petrus de Waal ◽  
Mohammed Balkhair ◽  
Ali Al-Mashikhi ◽  
Salem Khoom
Keyword(s):  
Habitat Preferences ◽  
Average Density ◽  
Suitable Habitat ◽  
Relative Probability ◽  
Conservation Areas ◽  
B Values ◽  
Urchin Density

Surveys were conducted along the eastern Dhofar coast of Oman to investigate densities and habitat preferences of juvenile Haliotis mariae (< 3 cm SL). Average density was 0.62 m-2 (SD 0.56); average urchin density was 3.4 urchins m-2 (SD 3.9). Relationships between juvenile abalone densities and small boulders (<30 cm in diameter (Ø)) tested significant (p = 0.049), as did those between juvenile abalone and urchin densities (p = 0.031). Selectivity (w) and standardized (B) ratios quantifying the relative probability of selection by juvenile abalone for different categories of resource available were calculated. For the studied area B values tested significantly different for (p = 0.004) the different habitats, urchins, boulders <30 cm, 30> <50 cm, and >50 cm Ø, respectively. B values were highest for urchins (6 times that for small boulders), and for boulders <30 cm Ø (double that for boulders 30> <50 cm Ø). B values for boulder habitats decreased as boulder size increased. Urchin utilisation by juvenile abalone as shelter ranged between geographic areas from a minimum of 15.5% to a maximum of 47.6%. The proportion of total habitat that is preferred by more than 97% of juvenile abalone found, including urchins and boulders < 50 cm Ø, comprises 29% of surveyed substratum. While the role urchins play on wild juvenile H. mariae has not proved vital, it is definitely significant. Although juvenile densities are low and are not currently limited by the availability of suitable habitat, it is crucial to identify and conserve those microhabitats that support recruitment of H. mariae. The abundance of these areas should be among the criteria used in selecting protected conservation areas.

Muskellunge Management: Fifty Years of Cooperation Among Anglers, Scientists, and Fisheries Biologists

2017 ◽  
Keyword(s):  
Aquatic Vegetation ◽  
Lake Michigan ◽  
Radio Telemetry ◽  
Habitat Preferences ◽  
Vegetation Coverage ◽  
Limiting Factor ◽  
Suitable Habitat ◽  
Spawning Habitat ◽  
Green Bay ◽  
Natural Reproduction

<em>Abstract</em>.—The identification, protection, and restoration of spawning habitat for Muskellunge <em>Esox masquinongy </em>in Green Bay, Lake Michigan are vital steps for re-establishing a self-sustaining population. This study was designed to locate spawning areas, document and model spawning habitat preferences, assess natural recruitment, and determine if suitable habitat was found throughout Green Bay (Fox River, lower Green Bay, Menominee River, and Little Sturgeon Bay). Radio transmitters were inserted into the oviduct of mature female Muskellunge prior to spawning and expelled transmitters were later located using radio telemetry to identify spawning locations. Between 2009 and 2010, 26 of 37 (70%) implanted transmitters were located as deposited at spawning locations. Using identified spawning locations, habitat selection was estimated for key environmental variables, and MaxEnt (maximum entropy) was utilized to model Muskellunge spawning habitat in the Menominee River, as it was the only study area where natural reproduction was documented. Menominee River Muskellunge showed significant preferences for spawning in areas with shallow bottom slopes (5%), with medium-to-high submerged aquatic vegetation coverage (>33%), where coarse woody debris was present, and where dominant substrates were sand or cobble. MaxEnt modeling predicted a ~2.5 magnitude greater likelihood of spawning at an average spawning location compared to an average background location. Comparisons of available habitat among study areas showed the Menominee River contained more spawning habitat with preferred characteristics. Results from this study are important steps in identifying spawning habitat as a potential limiting factor to successful Muskellunge reintroduction and models could be used to locate suitable areas to stock and guide delineation of critical spawning habitat to designate for protection.

Factors determining nematode distributions at Cape Hallett and Gondwana station, Antarctica

2013 ◽  
Vol 25 (3) ◽  
pp. 347-357 ◽  
Author(s):  
Mélianie R. Raymond ◽  
David A. Wharton ◽  
Craig J. Marshall
Keyword(s):  
Prey Availability ◽  
Habitat Preferences ◽  
Distribution Patterns ◽  
Organic Content ◽  
Salinity Range ◽  
Strong Impact ◽  
Dry Valleys ◽  
Soil Geochemistry ◽  
Conservation Areas ◽  
Low Salinity

AbstractThe distribution of nematodes at Cape Hallett and Gondwana station was found to be patchy but consistent, broad-scale habitat preferences were identified. These had been previously noted in McMurdo Dry Valleys soils and on Ross Island, indicating that habitat preferences are consistent across large scales and may play a role in determining range limits. Soil geochemistry, especially salinity, has a strong impact on distribution patterns. The distinct distribution patterns of the four species indicate different niches.Panagrolaimus davidiTimm is the only nematode that can survive within penguin rookeries, where salinity is high but bacterial food is plentiful.Scottnema lindsayaeTimm was found across the greatest range of habitats, including the driest sites and largest salinity range.Plectussp. was found in the wettest sites, with high organic content and low salinity.Eudorylaimus antarcticusSteiner (Yeates) was found at low densities and with other nematodes indicating a dependence on prey availability, an example of a biotic interaction structuring even these simplest ecosystems. Field-identifiable features could be used to identify probable nematode habitats, providing useful information for sampling and the selection of conservation areas.

scholarly journals Distribution, population density and habitat preferences of the Barn Owl (Tyto alba) in Sliven and Yambol districts, SE Bulgaria

2019 ◽  
Vol 2 ◽  
Author(s):  
Girgina Daskalova ◽  
Peter Shurulinkov ◽  
Georgi Popgeorgiev
Keyword(s):  
Habitat Preferences ◽  
Barn Owl ◽  
Average Density ◽  
Tyto Alba ◽  
Forest Patches ◽  
Rare And Endangered Species ◽  
Barn Owls ◽  
Rare And Endangered ◽  
Occupied Territories ◽  
Data Book

The Barn Owl (Tyto alba Gould, 1837) is a rare and endangered species in Bulgaria, included in the Red Data Book (Golemansky 2015) as “Vulnerable”, with national population estimated at 200–700 pairs. Barn Owl presence was surveyed using sound provocation during the night at 161 points in 52 small to medium-sized settlements in Sliven and Yambol districts (Thracian plain, SE Bulgaria). The studied territory was about 1190 km2. The habitats presented in a 3-km radius around the presence and potential absence points were statistically analysed. The species was found to be a quite common breeding species in the study area – a total of 56 Barn Owls were registered, at 50 points (31.1%), in 31 settlements (62% of all studied). Clear defensive behavior was observed against the source of the sound in many occasions. The average density of the population was 4.2 occupied territories / 100 km2. The occupied locations were situated mostly in settlements laying in deforested lowland areas (far from large forest patches), with flat or hilly relief, covered by agricultural lands, pastures and steppes. The number of presences was found to be scarce in villages along heavily used motorways. Traffic-caused mortality of Barn Owls is commented as a probable explanation.

scholarly journals Mapping the potential distribution of the Critically Endangered Himalayan Quail Ophrysia superciliosa using proxy species and species distribution modelling

2015 ◽  
Vol 25 (4) ◽  
pp. 466-478 ◽  
Author(s):  
JONATHON C. DUNN ◽  
GRAEME M. BUCHANAN ◽  
RICHARD J. CUTHBERT ◽  
MARK J. WHITTINGHAM ◽  
PHILIP J. K. MCGOWAN
Keyword(s):  
Land Cover ◽  
Species Distribution ◽  
Climate Model ◽  
Habitat Preferences ◽  
Species Distribution Modelling ◽  
Critically Endangered ◽  
Suitable Habitat ◽  
Distribution Models ◽  
Extant Species ◽  
Starting Point

SummaryThe Critically Endangered Himalayan Quail Ophrysia superciliosa has not been reliably recorded since 1876. Recent searches of historical sites have failed to detect the species, but we estimate an extinction year of 2023 giving us reason to believe that the species may still be extant. Species distribution models can act as a guide for survey efforts, but the current land cover in the historical specimen record locations is unlikely to reflect Himalayan Quail habitat preferences due to extensive modifications. Thus, we investigate the use of two proxy species: Cheer Pheasant Catreus wallechi and Himalayan Monal Lophophorus impejanus that taken together are thought to have macro-habitat requirements that encapsulate those of the Himalayan Quail. After modelling climate and topography space for the Himalayan Quail and these proxy species we find the models for the proxy species have moderate overlap with that of the Himalayan Quail. Models improved with the incorporation of land cover data and when these were overlaid with the Himalayan Quail climate model, we were able to identify suitable areas to target surveys. Using a measure of search effort from recent observations of other galliformes, we identify 923 km2 of suitable habitat surrounding Mussoorie in Northern India that requires further surveys. We conclude with a list of five priority survey sites as a starting point.

scholarly journals Landscape Scale and Microhabitat of the Endangered New Mexico Meadow Jumping Mouse in the White Mountains, Arizona

2017 ◽  
Vol 8 (1) ◽  
pp. 39-58
Author(s):  
Jennifer K. Frey
Keyword(s):  
New Mexico ◽  
San Francisco ◽  
Habitat Preferences ◽  
Capture Rate ◽  
High Elevation ◽  
American Southwest ◽  
Habitat Associations ◽  
Livestock Grazing ◽  
Suitable Habitat ◽  
White Mountains

Abstract The New Mexico meadow jumping mouse Zapus hudsonius luteus was listed as endangered under the U.S. Endangered Species Act in 2014, with critical habitat designated in 2016. Despite these recent conservation actions, there is a paucity of published information regarding its habitat associations. The taxon is a riparian obligate that occurs along both low-elevation rivers and high-elevation headwater streams in several disjunct areas of the American Southwest. Habitat information from one region might not apply to others. The distribution and habitat preferences of the New Mexico meadow jumping mouse in the White Mountains in eastern Arizona are poorly known. Objectives of this study were to 1) identify and resurvey historical locations in the White Mountains, 2) survey for new populations in areas with potentially suitable habitat in the White Mountains, and 3) use quantitative data to evaluate habitat associations at the landscape and microhabitat scales and to compare habitat at sites where I captured or did not capture the New Mexico meadow jumping mouse. I found 123 historical records of the New Mexico meadow jumping mouse from 21 locations in the White Mountains, indicating a formerly broad distribution. I conducted field surveys and collected habitat data at 35 sites (14 historical, 21 new) and caught 37 (39 total captures) New Mexico meadow jumping mice at 12 sites, including 6 of 12 historical locations surveyed. The overall capture rate was 0.36%, with an average capture rate at sites where it was present of 1.28% (range = 0.25–2.5%). All historical sites where I caught the New Mexico meadow jumping mouse were in the drainage of the Black River. The six new sites included the first records for Nutrioso Creek and Corduroy Creek and confirmed persistence of the taxon in the East Fork Little Colorado River, San Francisco River, and Blue River watersheds. Habitat used by the New Mexico meadow jumping mouse in the White Mountains was similar to that reported for other montane populations, characterized by tall, dense herbaceous vegetation composed primarily of forbs and sedges on saturated soil in close proximity to flowing water. However, there was significantly more cover provided by alders Alnus spp. at capture sites at both the stream reach and microhabitat scales. All sites where I captured the New Mexico meadow jumping mouse had no authorized livestock grazing, and the taxon was more likely to occur at sites where there were no signs of unauthorized livestock grazing. Further, there was a significant positive relationship between alder cover and time since an area was excluded from livestock grazing. The widespread exclusion of livestock from riparian areas in the White Mountains may have contributed to the higher rate of population persistence of the New Mexico meadow jumping mice in the White Mountains compared with the Jemez and Sacramento mountains, New Mexico. Although the overall persistence rate in the White Mountains (47%) was higher than other populations, the population is at risk of further losses due to small, isolated occupied areas and ongoing threats.

scholarly journals Habitat preference and potential distribution of Magnolia officinalis subsp. officinalis and M. o. subsp. biloba in China

2019 ◽  
Vol 36 ◽  
pp. 93-111
Author(s):  
Chuangye Song ◽  
Huiming Liu ◽  
Jixi Gao
Keyword(s):  
Human Disturbance ◽  
Environmental Variables ◽  
Potential Distribution ◽  
Habitat Preferences ◽  
Extreme Temperatures ◽  
Conservation Areas ◽  
Suitable Habitats ◽  
Magnolia Officinalis ◽  
The Relationship ◽  
Selection Of

Magnolia officinalis subsp. officinalis and M. officinalis subsp. biloba are important medicinal plants in China. The bark of these two subspecies is commonly used in the production of a widely-used Chinese traditional medicine named ‘Houpu’. In recent years, M. o. subsp. officinalis and M. o. subsp. biloba have become increasingly threatened owing to the over-harvesting of their bark and the fragmentation of their habitats. In this study, we aimed to support the conservation and cultivation of these two subspecies in China by: (1) assessing the relationship between numerous environmental variables and the geographical distributions of the subspecies; (2) analysing the environmental characteristics of suitable habitats for both subspecies and predicting the spatial distribution of these habitats in China; and (3) identifying conservation areas of both subspecies in China via overlay analysis. We also assessed the degree of human disturbance within suitable habitats. We found that temperature was a major determinant for the distribution of M. o. subsp. officinalis. Conversely, the distribution of M. o. subsp. biloba was primarily dependent on precipitation rather than temperature. Distinct habitat preferences were observed between M. o. subsp. officinalis and M. o. subsp. biloba. Suitable habitats of M. o. subsp. officinalis were primarily distributed in the northern subtropical areas of China, with greater fluctuations in ambient temperature, lower extreme temperatures, less precipitation and greater fluctuations in precipitation. Habitats suitable for M. o. subsp. biloba were highly fragmented and were distributed in the central subtropical areas of China. We found that a large proportion of suitable habitats were not in the protected areas and that they were significantly disturbed by human activity. This analysis could provide useful information for the conservation of both M. o. subsp. officinalis and M. o. subsp. biloba and could aid in the selection of cultivation sites.

scholarly journals Bandicoots return to Booderee: initial survival, dispersal, home range and habitat preferences of reintroduced southern brown bandicoots (eastern sub species; Isoodon obesulus obesulus)

2018 ◽  
Vol 45 (2) ◽  
pp. 132 ◽  
Author(s):  
N. M. Robinson ◽  
C. I. MacGregor ◽  
B. A. Hradsky ◽  
N. Dexter ◽  
D. B. Lindenmayer
Keyword(s):  
Home Range ◽  
Body Mass ◽  
National Park ◽  
Effective Means ◽  
Habitat Preferences ◽  
Home Range Size ◽  
Suitable Habitat ◽  
Home Ranges ◽  
Vegetation Types ◽  
Eastern Australia

Context Reintroductions can be an effective means of re-establishing locally extinct or declining faunal populations. However, incomplete knowledge of variables influencing survival and establishment can limit successful outcomes. Aim We aimed to examine the factors (e.g. sex, body mass, release order) influencing the survival, dispersal, home range and habitat selection of reintroduced southern brown bandicoots (eastern subspecies; Isoodon obesulus obesulus) into an unfenced, predator-managed environment in south-eastern Australia (Booderee National Park). Methods Over 2 weeks in May 2016, six female and five male bandicoots were wild-caught in state forest and hard released into the park. Release locations were approximately evenly distributed between three primary vegetation types assessed as suitable habitat: heath, woodland and forest. Bandicoots were radio-tracked day and night for 4 weeks from the initial release date. Key results No mortality was detected. Males dispersed more than twice as far as females (male 704 m, female 332 m), but there was no significant sex bias in home range size. At the landscape scale, bandicoots preferentially selected home ranges that contained heath and avoided forest. Within home ranges, heath and woodland were both favoured over forest. Conclusions Post-release dispersal is sex-biased, but more data are required to determine the influence of other predictors such as body mass and release order. Within the release area, bandicoots favoured non-forest vegetation types. Implications Our study outlines factors influencing the establishment of reintroduced bandicoots. We recommend that future bandicoot reintroductions to Booderee National Park occur within areas of heath and woodland, and that subsequent releases consider the potentially larger spatial requirements and conspecific avoidance among male bandicoots. Our findings contribute new knowledge for improving translocation methods of a nationally endangered medium-sized mammal.

scholarly journals Better providers of habitat for Javan slow loris (Nycticebus javanicus E. Geoffroy 1812): A species distribution modeling approach in Central Java, Indonesia

2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Mahfut Sodik ◽  
Satyawan Pudyatmoko ◽  
Pujo Semedi Hargo Yuwono ◽  
Muhammad Tafrichan ◽  
Muhammad Ali Imron
Keyword(s):  
Species Distribution ◽  
Species Distribution Modeling ◽  
Distribution Model ◽  
Suitable Habitat ◽  
Conservation Areas ◽  
Slow Loris ◽  
Modeling Approach ◽  
Central Java ◽  
Distribution Modeling ◽  
Central Java Province

Abstract. Sodik M, Pudyatmoko S, Yuwono PSH, Tafrichan M, Imron MA. 2020. Better providers of habitat for Javan slow loris (Nycticebus javanicus E. Geoffroy 1812): A species distribution modeling approach in Central Java, Indonesia. Biodiversitas 21: 1890-1900. The Javan slow loris is an arboreal and nocturnal primate endemic to Java, which is known to inhabit primary and secondary forest habitats, such as swamps, plantations, and bamboo forest. The population of the Javan slow loris continues to decline significantly due to forest degradation, habitat loss/fragmentation, and illegal trade. Conservation of this small primate in Java has been hampered by a paucity of local data on how conservation areas support this species. This study aims to build a spatial distribution model of the Javan slow loris and analyzing the role of each stakeholder plays on land use type to support the conservation of N. javanicus. By utilizing Species Distribution Modeling (SDM) with Maximum Entropy species distribution modeling approach, the researchers were able to highlight the importance of which conservation areas in Central Java that play crucial role to conserve the N. javanicus population. Data on the presence of the Javan slow loris was obtained from the result of a survey undertaken in 2017 and communication with researchers. Elevation, slope, landcover, rainfall, distance to road, distance to settlement, distance to river (water source), and NDVI were used as environmental variables. Results showed that 0.76% (25,715.4 ha) of the total area of the Central Java Province is suitable for their habitat. In addition, results revealed that 2.2% of suitable habitat is present within conservation areas, 4.6% in protected forest areas, and 93.2% outside of protected areas. The Javan slow loris is predicted to be mostly scattered in the northern part of Central Java Province. The Javan slow loris is widely distributed in plantations, their most dominant habitat. The findings of this study show that the small percentage of suitable habitat presents within protected forest and conservation areas cannot sustainably maintain the extant Javan slow loris population. Thus, it is important for the Indonesian government and other key related stakeholders to work together in combination with educating local communities to preserve the habitat and population of N. javanicus.

scholarly journals Identifying priority conservation areas for recovering large carnivores using citizen science data

2018 ◽  
Author(s):  
A-S. Bonnet-Lebrun ◽  
A.A. Karamanlidis ◽  
M. de Gabriel Hernando ◽  
I. Renner ◽  
O. Gimenez
Keyword(s):  
Protected Areas ◽  
Citizen Science ◽  
Process Model ◽  
Conservation Priorities ◽  
Suitable Habitat ◽  
Spatial Processes ◽  
Conservation Areas ◽  
Science Data ◽  
Anthropogenic Landscapes ◽  
Brown Bears

AbstractUnderstanding the processes related to wildlife recoveries is not only essential in solving human – wildlife conflicts, but also for identifying priority conservation areas and in turn, for effective conservation planning. We used data from a large citizen science program to study the spatial processes related to the demographic and genetic recovery of brown bears in Greece and to identify new areas for their conservation. This was achieved by visually comparing our data with an estimation of the past distribution of brown bears in Greece and by using a Point Process Model to model habitat suitability, and then comparing our results with the current distribution of brown bear records and with that of protected areas. Our results indicate that in the last 15 years bears may have increased their range by as much as 100%, by occupying mainly anthropogenic landscapes and areas with suitable habitat that are currently not legally protected, thus creating a new conservation reality for the species in Greece. This development dictates the re-evaluation of the national management and conservation priorities for brown bears in Greece by focusing in establishing new protected areas that will safeguard their recovery. Our conservation approach is a swift and cheap way of identifying priority conservation areas, while gaining important insights on the spatial processes associated with population recoveries. It will help prioritize conservation actions for brown bears in Greece and may serve as a model conservation approach to countries facing financial and logistic constraints in the monitoring of local biodiversity or facing challenges in managing rapid population recoveries. Our conservation approach appeared also to be better suited to identifying priority areas for conservation in areas with recovering wildlife populations and may therefore be used as an “early-warning” conservation system.

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