General Habitat Preferences Research Articles

Spiders of the Udmurt Republic, Russia.

BackgroundThe long-term project "Spiders of the Udmurt Republic" (2007–2018) aimed to research spiders' regional fauna and zoogeography, diversity (including spatial and seasonal patterns) and habitat preferences. We performed the collection of spiders in all natural zones of the republic, habitats and vegetation layers, both at permanent sampling plots and through ad-hoc sampling en route.New informationThe dataset includes occurrences from 53 geographical points with 10,500 records and more than 35,000 specimens. This increases the existing data on Russian spiders on GBIF by four times, from 11,000 (excluding iNaturalist observations) to 46,000. The dataset allows for the exploration of regional fauna, local and general species distribution, spider phenology and habitat preferences for the purposes of monitoring and conservation.

Convergent evolution of karst habitat preference and its ecomorphological correlation in three species of Bent-toed Geckos (Cyrtodactylus) from Peninsular Malaysia

Abstract By studying ecomorophology in the context of phylogeny, researchers can parse out similarity due to common ancestry versus that due to convergence. This is especially true among relatively closely related species where both phylogenetic and environmental constraints may be operating simultaneously. We explored these issues among three karst-associated species from two lineages of Cyrtodactylus—the sworderi group from Peninsular Malaysia and the swamp clade from Peninsular Malaysia and western Indonesia of the agamensis group. A stochastic character mapping analysis using five different habitat preferences corroborated a larger previous analysis in recovering a general habitat preference as an ancestral condition for all habitat preferences and a karst habitat preference in C. guakanthanensis and C. gunungsenyumensis of the sworderi group and C. metropolis of the swamp clade as convergently evolved. Multivariate and univariate analyses of 10 morphometric characters revealed that the ecomorphological similarity between C. guakanthanensis and C. gunungsenyumensis of the sworderi group was also convergent. The ecomorphology of C. metropolis of the swamp clade was intermediate between a karst-adapted ecomorphology and a swamp-generalists ecomorphology. Of the 10 morphometric characters employed in this analysis, only three—head length, head width, and forelimb width—showed any signs of phylogenetic signal. Cyrtodactylus metropolis is hypothesized to be a recently refuged swamp-dwelling species that frequented the Batu Caves environments prior to urbanization of the surrounding swamp habitat to which it is now confined.

Karstic Landscapes Are Foci of Species Diversity in the World’s Third-Largest Vertebrate Genus Cyrtodactylus Gray, 1827 (Reptilia: Squamata; Gekkonidae)

Karstic landscapes are immense reservoirs of biodiversity and range-restricted endemism. Nowhere is this more evident than in the world’s third-largest vertebrate genus Cyrtodactylus (Gekkonidae) which contains well over 300 species. A stochastic character mapping analysis of 10 different habitat preferences across a phylogeny containing 344 described and undescribed species recovered a karst habitat preference occurring in 25.0% of the species, whereas that of the other eight specific habitat preferences occurred in only 0.2–11.0% of the species. The tenth category—general habitat preference—occurred in 38.7% of the species and was the ancestral habitat preference for Cyrtodactylus and the ultimate origin of all other habitat preferences. This study echoes the results of a previous study illustrating that karstic landscapes are generators of species diversity within Cyrtodactylus and not simply “imperiled arks of biodiversity” serving as refugia for relics. Unfortunately, the immense financial returns of mineral extraction to developing nations largely outweighs concerns for biodiversity conservation, leaving approximately 99% of karstic landscapes with no legal protection. This study continues to underscore the urgent need for their appropriate management and conservation. Additionally, this analysis supports the monophyly of the recently proposed 31 species groups and adds one additional species group.

The influence of habitat preference on longitudinal population composition and distribution of Groupers (Serranidae) in Chumbe Island Coral Park, Zanzibar, Tanzania

A survey of six common grouper (Serranidae) species was conducted on both the western protected and eastern unprotected reefs around Chumbe Island, Zanzibar. Species, estimated maturity, and habitat were recorded using standardized categories. Fundamental niche and general habitat preference were extrapolated based on observed realized niche and qualified based on substrate, depth, slope position, and general reef region. Taking habitat preference into account, abundance and biomass density of serranid populations were compared between locations on the reef in order to best account for how habitat influences distribution and population health. The results of this study provide depth to previous research on the protected reef and indicate noteworthy shifts in population composition between 2014 and 2018 that favour species with less specified habitat preference, such as Aethaloperca rogaa and Cephalopholis argus. Surveys of Chumbe’s nearby unprotected eastern reef indicate low levels of species abundance, which this study hypothesizes is the result of inappropriate habitat structure, increased fishing pressure, and decreased population health within the MPA. Ultimately, this study suggests that MPAs do not protect all species equally, and habitat preference must be taken into account when assessing MPA effectiveness at protecting different species. Indeed, especially as serranid habitat faces continued degradation, serranid conservation will depend even more on protection of each species’ preferred habitat in coral systems. As such, assessing serranid populations as a whole fails to capture the changes in population distribution and composition that is occurring between species, which may be more indicative of shifts and disturbances in the ecosystem.

Evolution of habitat preference in 243 species of Bent-toed geckos (Genus Cyrtodactylus Gray, 1827) with a discussion of karst habitat conservation.

Understanding the processes that underpin adaptive evolutionary shifts within major taxonomic groups has long been a research directive among many evolutionary biologists. Such phenomena are best studied in large monophyletic groups that occupy a broad range of habitats where repeated exposure to novel ecological opportunities has happened independently over time in different lineages. The gekkonid genus Cyrtodactylus is just such a lineage with approximately 300 species that range from South Asia to Melanesia and occupy a vast array of habitats. Ancestral state reconstructions using a stochastic character mapping analysis of nine different habitat preferences were employed across a phylogeny composed of 76% of the known species of Cyrtodactylus. This was done in order to ascertain which habitat preference is the ancestral condition and from that condition, the transition frequency to more derived habitat preferences. The results indicate that a general habitat preference is the ancestral condition for Cyrtodactylus and the frequency of transitioning from a general habitat preference to anything more specialized occurs approximately four times more often than the reverse. Species showing extreme morphological and/or ecological specializations generally do not give rise to species bearing other habitat preferences. The evolution of different habitat preferences is generally restricted to clades that tend to occur in specific geographic regions. The largest radiations in the genus occur in rocky habitats (granite and karst), indicating that the transition from a general habitat preference to a granite or karst‐dwelling life style may be ecologically uncomplicated. Two large, unrelated clades of karst‐associated species are centered in northern Indochina and the largest clade of granite‐associated species occurs on the Thai‐Malay Peninsula. Smaller, independent radiations of clades bearing other habitat preferences occur throughout the tree and across the broad distribution of the genus. With the exception of a general habitat preference, the data show that karst‐associated species far out‐number all others (29.6% vs. 0.4%–10.2%, respectively) and the common reference to karstic regions as “imperiled arcs of biodiversity” is not only misleading but potentially dangerous. Karstic regions are not simply refugia harboring the remnants of local biodiversity but are foci of speciation that continue to generate the most speciose, independent, radiations across the genus. Unfortunately, karstic landscapes are some of the most imperiled and least protected habitats on the planet and these data continue to underscore the urgent need for their conservation.

A new species of Cyrtodactylus Gray (Squamata; Gekkonidae) from the ThaiHighlands with a discussion on the evolution of habitat preference.

A new gekkonid lizard, Cyrtodactylus maelanoi sp. nov., from Mae Hong Son Province of the Thai Highlands is described using an integrative taxonomic analysis based on morphology, color pattern, and the mitochondrial gene NADH dehydrogenase subunit 2 (ND2) and its flanking tRNAs. Phylogenetic analyses place the new species within clade 1 of the C. sinyineensis group and as the sister species to C. inthanon with an uncorrected pairwise sequence divergence of 3.9%. Collection data gathered in the field indicate that C. maelanoi sp. nov. is a habitat generalist. Reconstruction of the ancestral habitat preference for the C. sinyineensis group by way of stochasitc character mapping (SCM) indicates that karstic environments were the ancestral condition out of which the general habitat preference of the ancestor of C. maelanoi sp. nov. and C. inthanon and that of C. amphipetreaus and C. doisuthep evolved three times independently. Additionally, SCM demonstrated that the evolution of a granitic habitat preference from a karst-adapted ancestor happened in C. aequalis. The discovery of a new upland species in the Thai Highlands brings into focus the understudied nature of the mountain systems of western Thailand and the need for their continued exploration and conservation.

A new insular species of the Cyrtodactylus intermedius (Squamata: Gekkonidae)group from Cambodia with a discussion of habitat preference and ecomorphology.

An integrative taxonomic analysis based on mitochondrial and morphological data recovered the population of Cyrtodactylus on Koh Rong Island, Preah Sihanouk Province, Cambodiaa as an endemic insular species belonging to the Cyrtodactylus intermedius group. This brings the number of species in the C. intermedius group to at least 10 and the number of species in Cambodia to at least seven. Species of this relatively small group vary widely in habitat preference, occurring in general, terrestrial, karstic, or granitic habitats. Ancestral character state mapping recovered a general habitat preference as the ancestral condition from which all others independently evolved even though this did not covary with morphology. The description of another new species of reptile from Cambodia continues to underscore the potentially significant amount of unrealized biodiversity in Indochina and Southeast Asia and the continued need for field surveys in unexplored or poorly explored areas.

Current state and historical notes on sand dune flora of the Bulgarian Black Sea Coast

This study is the first overview of the floristic diversity of Bulgarian coastal dunes in terms of the presence of typical psammophytic or non-psammophytic plant species. It also aims to reveal changes in sand dune flora over time, based on own samples and existing data from previous studies. Our original floristic data was extracted from 154 phytosociological plots sampled in 12 large dune systems during 2017. All available literature sources were compiled to derive a list of vascular plants recorded for Bulgarian coastal dunes between 1905 and 2016. Due to the different scientific approaches applied in previous publications we split the studies into three periods over time: (I period: 1905 1950; II period: 1951–1990; III period: 1991–2016), and separate lists were also prepared for each. All vascular plants were assigned to one of five groups, according to their general habitat preference: 1) psammophytes, 2) weeds and ruderals, 3) grass- and shrubland plants, 4) forests plants and 5) alien (including invasive) species. The full species list comprises 501 taxa, and the highest number of species was compiled from publications after 1990. Across all periods and studied dune complexes, grass- and shrubland plants were most abundant, while other non-psammophyte species groups showed low presence. A comparison of data from 2003 and 2015 showed that species richness of psammophytes decreased over time, which is in contrast to the average number of weeds and ruderals, and particularly to species richness of grass- and shrubland species. Our results show that a core group of characteristic psammophytes remains constant through all study periods. Alien (including invasive) species still are limited in abundance but there is an alarming recent increase in their numbers. We believe that our synthesis will be of use for further floristic inventories of Pontic sand dunes.

Comparative phylogeography of mainland and insular species of Neotropical molossid bats (Molossus).

Historical events, habitat preferences, and geographic barriers might result in distinct genetic patterns in insular versus mainland populations. Comparison between these two biogeographic systems provides an opportunity to investigate the relative role of isolation in phylogeographic patterns and to elucidate the importance of evolution and demographic history in population structure. Herein, we use a genotype‐by‐sequencing approach (GBS) to explore population structure within three species of mastiff bats (Molossus molossus, M. coibensis, and M. milleri), which represent different ecological histories and geographical distributions in the genus. We tested the hypotheses that oceanic straits serve as barriers to dispersal in Caribbean bats and that isolated island populations are more likely to experience genetic drift and bottlenecks in comparison with highly connected ones, thus leading to different phylogeographic patterns. We show that population structures vary according to general habitat preferences, levels of population isolation, and historical fluctuations in climate. In our dataset, mainland geographic barriers played only a small role in isolation of lineages. However, oceanic straits posed a partial barrier to the dispersal for some populations within some species (M. milleri), but do not seem to disrupt gene flow in others (M. molossus). Lineages on distant islands undergo genetic bottlenecks more frequently than island lineages closer to the mainland, which have a greater exchange of haplotypes.

Crop diversity loss as primary cause of grey partridge and common pheasant decline in Lower Saxony, Germany.

BackgroundThe grey partridge (Perdix perdix) and the common pheasant (Phasianus colchicus) are galliform birds typical of arable lands in Central Europe and exhibit a partly dramatic negative population trend. In order to understand general habitat preferences we modelled grey partridge and common pheasant densities over the entire range of Lower Saxony. Spatially explicit developments in bird densities were modelled using spatially explicit trends of crop cultivation. Pheasant and grey partridge densities counted annually by over 8000 hunting district holders over 10 years in a range of 3.7 Mio ha constitute a unique dataset (wildlife survey of Lower Saxony). Data on main landscape groups, functional groups of agricultural crops (consisting of 9.5 million fields compiled by the Integrated Administration and Control System) and landscape features were aggregated to 420 municipalities. To model linear 8 or 10 year population trends (for common pheasant and grey partridge respectively) we use rho correlation coefficients of densities, but also rho coefficients of agricultural crops.ResultsAll models confirm a dramatic decline in population densities. The habitat model for the grey partridge shows avoidance of municipalities with a high proportion of woodland and water areas, but a preference for areas with a high proportion of winter grains and high crop diversity. The trend model confirms these findings with a linear positive effect of diversity on grey partridge population development. Similarly, the pheasant avoids wooded areas but showed some preference for municipalities with open water. The effect of maize was found to be positive at medium densities, but negative at very high proportions. Winter grains, landscape features and high crop diversity are favorable. The positive effect of winter grains and higher crop diversity is also supported by the trend model.ConclusionsThe results show the strong importance of diverse crop cultivation. Most incentives favor the cultivation of specific crops, which results in large areas of monocultures. The results confirm the importance of sustainable agricultural policies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12898-016-0093-9) contains supplementary material, which is available to authorized users.

Butterfly monitoring using systematically placed transects in contrasting climatic regions – exploring an established spatial design for sampling

Butterfly monitoring schemes are recording programs initiated to monitor nationwide butterfly abundance and distribution patterns, often with help from volunteers. The method generates high-resolution data, but may be associated with a degree of habitat sampling bias if volunteers prefer to survey areas perceived to be high-quality butterfly habitats. This can result in habitats becoming underrepresented in the data set, leading to less information about the butterfly populations there. In the present study, we investigate the possibility of applying a spatial design used by the Swedish Bird Survey for nationwide, gridbased sampling, with a goal to get butterfly monitoring data covering a representative sample of different habitats. We surveyed four 2×2 km sampling squares, split into 100 m segments, in the southernmost region of Sweden (Scania) and four in the northernmost region (Norrbotten). The grid-based transects were compared with volunteer-selected transects in a G IS analysis using a refined Swedish version of CORINE land cover data to see how well these two transect designs represent true habitat coverage. A total of 53 km transect was monitored, resulting in 490 individuals and 29 different species recorded. We found that transect cover correlated significantly with overall land cover using both monitoring methods, though standardised transects outperformed volunteer-selected transects in habitat representation in Scania, but not in Norrbotten. Butterflies were found to aggregate significantly in specific habitats, but with contrasting results for the two geographically different regions. Grasslands in both regions generated a high number of recorded butterflies, although so did clear-cut and residential areas in Norrbotten as well. The highest number of individuals recorded per transect was found in bogs in Scania. This study emphasises the value of complementing free site selection monitoring schemes with spatially representative schemes such as the Swedish Bird Survey, and sheds some light on general habitat preferences for Swedish butterflies in two contrasting climatic regions. Copyright Elin Videvall et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. (Less)

Comparative genetic structure of sympatric leporids in southern Illinois

Abstract Many leporid species have overlapping ranges, but ecological differences may make for profoundly different population structure in the same area. In southern Illinois, swamp rabbits (Sylvilagus aquaticus) and eastern cottontails (S. floridanus) co-exist, but swamp rabbits are habitat specialists associated with floodplain forests and eastern cottontails exhibit more general habitat preferences. Additionally, swamp rabbits exist at the northern edge of their range in southern Illinois, whereas eastern cottontails are well within the core of their range. To determine whether these differences resulted in differences in genetic structure, we assessed the population differentiation of these 2 sympatric species in southern Illinois using polymorphic microsatellite markers. We employed a combination of sampling techniques including tissue sampling from trapped rabbits and collection of fecal pellets from swamp rabbit latrine logs. Swamp rabbits appeared to be differentiated within 50 km of Illinois’ Cache River watershed (K = 4 populations) suggesting that local populations are relatively isolated, whereas eastern cottontails exhibited no discernable genetic structure (K = 1). Such a result confirms the expected relationship of greater genetic structure in a habitat specialist (i.e., swamp rabbits) versus a habitat generalist (i.e., eastern cottontails). Unlike eastern cottontails, our results suggest that swamp rabbits experience low genetic connectivity in southern Illinois likely due to restricted dispersal, linear distribution of habitat, and smaller effective population size as mediated by habitat fragmentation.

Tortula randii(Pottiaceae) New for Slovakia and Comments on Its Distinction fromTortula cernua

Abstract: Muller, F. 2014. Tortula randii (Pottiaceae) new for Slovakia and comments on its distinction from Tortula cernua. — Herzogia 27: 413–417. The rare moss Tortula randii(Desmatodon randii) is reported as new for Slovakia from the area of a travertine spring in the district of Levoca. The species grows here in the halophilous community Scorzonero parviflorae-Juncetum gerardii together with other halophilous vascular plants and mosses. General distribution and habitat preferences of the species are summarized. Sometimes, especially from North American bryologists, T. randii is treated as a synonym of T. cernua. Based on literature reports and field observations, T. randii is distinct and worthy of species recognition.

Contribution to the flora of Asian and European countries: new national and regional vascular plant records

The paper presents new records for 10 vascular plant species from three Asian and four European countries. Of this number, three species (Panicum capillare, Stipa macroglossa, Tribulus longipetalus) are reported from Tajikistan, two (Calamagrostis emodensis, Calamagrostis lahulensis) from Myanmar, two (Euphorbia taurinensis, Origanum vulgare var. megastachyum) from Poland, one (Sagina apetala) from Uzbekistan, one (Orobanche ritro) from Ukraine and Russia, and one (Leontodon saxatilis) from the Czech Republic. Eight of these taxa are new to the flora of different Asian and European countries; and two, very rare but recently spreading species, namely Leontodon saxatilis and Euphorbia taurinensis, were reported from the Czech Republic and Poland, respectively. Four of the taxa presented (Euphorbia taurinensis, Panicum capillare, Sagina apetala and Tribulus longipetalus) should be regarded as alien to the studied areas, intensively spreading or even invasive, whereas the other six are native elements given for the first time from the countries. In each of the species, synonyms, the general distribution, habitat preferences and habitats occupied in the particular country, taxonomy with remarks on recognition and differentiating the species from the most similar occurring in particular country as well as a list of localities of examined species occurring in a given country, often far from the previously known areas, were presented. In the case of Stipa macroglossa a lectotype for the species was designated in the present paper. Illustrations for Stipa macroglossa and Orobanche ritro were also provided.

Modelling the distribution of the pan‐continental invasive fish Pseudorasbora parva based on landscape features in the northern Kyushu Island, Japan

ABSTRACT Topmouth gudgeon (Pseudorasbora parva) is widely known as a highly invasive freshwater fish and has expanded from East Asia (native range) to Central Asia, Europe and Northern Africa (introduced range). Although the relationship between the occurrence of P. parva and its habitat conditions remains unclear, information on factors affecting its distribution, especially in its native range, is important for predicting its expansion. This study provides primary information on the distribution of P. parva in rivers and agricultural canals in northern Kyushu Island, Japan, where the fish is native. Fuzzy habitat preference models (FHPMs) and Random Forests (RF) were applied to link landscape features to the distribution of P. parva based on field observation data collected from two distinct ecoregions, the north‐western (NW) and north‐eastern (NE) parts of Kyushu Island. The results show a clear habitat preference of P. parva for areas with a lower elevation, a gentler slope and a smaller number of river‐to‐river connections as general landscape features across the ecoregions. Weak preferences are observed for sites with a higher number of river‐to‐canal connections, a higher canal network index, a larger area of paddy fields, a larger residential area, more crop fields and fewer forests and orchards. Of these site‐specific features, five landscape features – elevation, slope, canal network index, area of paddy fields, and presence of forests and orchards – are identified as the most important features for predicting the distribution of P. parva. The general and specific habitat preference information, as demonstrated in this study, may be important in biogeography and invasion ecology. Further research is needed to accumulate information for a better understanding of the invasion ecology and the design of improved management and control strategies against P. parva. Copyright © 2013 John Wiley & Sons, Ltd.

Spatial fidelity of skeletal remains: elk wintering and calving grounds revealed by bones on the Yellowstone landscape

The spatial distributions of bones on landscape surfaces (death assemblages) may contain high-quality data on species' landscape use. Previous investigations into the spatial fidelity of death assemblages focused on general habitat preferences of the source community. Using well-studied elk populations of Yellowstone National Park, I test the geographic sensitivity of death assemblages by assessing the fidelity of shed elk antlers to the distribution of bull elk in late winter (documented through aerial surveys). I also test the geographic fidelity of newborn calf bones to known calving areas. The spatial distribution of antlers is highly faithful to bull elk landscape use, describing the decadally averaged distribution of wintering grounds as well or better than individual aerial surveys. Discrepancies in geographic distributions between recent wintering patterns and the multi-decadal antler assemblage also suggests differences in winter landscape use between current and historical (wolf-free) populations. Neonatal remains, including those partially consumed by carnivores, were always recovered in known calving areas, and all sampled calving grounds produced neonatal bones. Bone surveys are a new, minimally invasive, low-impact tool for obtaining high-quality historically informed data on species' geographic and habitat requirements. This tool will be particularly useful for managing sensitive species, fragile ecosystems, and poorly studied regions.

Parallel habitat specialization within the wolf spider genusHognafrom the Galápagos

Within most island archipelagos, such as the Galápagos, similar ecological gradients are found on geographically isolated islands. Species radiations in response to these ecological gradients may follow different scenarios being (i) a single habitat specialization event followed by secondary colonization of each ecotype on the different islands or (ii) repeated and parallel habitat specialization on each island separately. This latter scenario has been considered less likely as gene flow might hamper such ecotypic differentiation. At least for the Galápagos, the extent to which this process is involved in species radiations remains yet poorly understood. Within the wolf spider genus Hogna, seven species are described that can be divided into three different ecotypes based on general morphology and habitat preference i.e. species that inhabit the pampa vegetation in the highlands, species that occur in coastal dry habitats and one generalist species. Comparison of the species phylogeny based on one mitochondrial (COI) and one nuclear (28S) gene fragment convincingly demonstrates that 'pampa' and 'coastal dry' species evolved in parallel on the islands Santa Cruz and San Cristóbal. Despite the observation that allozymes analysis indicated that each species forms a distinct genetic cluster, phylogenetic divergence within these species complexes was very low and paraphyletic and most likely due to hybridization rather than incomplete lineage sorting, as demonstrated for the Santa Cruz species complex. This suggests that within-island speciation occurred under low levels of gene flow. Species phylogeny in general did not follow the progression of island emergence as a molecular clock analysis suggested that island endemic species may have diverged after as well as before the emergence of the islands. This represents the first clear example of parallel and within-island speciation because of habitat specialization on the Galápagos and that such divergence most likely occurred under historic gene flow.

Modeling the Relations Between Flow Regime Components, Species Traits, and Spawning Success of Fishes in Warmwater Streams

Modifications to stream hydrologic regimes can have a profound influence on the dynamics of their fish populations. Using hierarchical linear models, we examined the relations between flow regime and young-of-year fish density using fish sampling and discharge data from three different warmwater streams in Illinois, Alabama, and Georgia. We used an information theoretic approach to evaluate the relative support for models describing hypothesized influences of five flow regime components representing: short-term high and low flows; short-term flow stability; and long-term mean flows and flow stability on fish reproductive success during fish spawning and rearing periods. We also evaluated the influence of ten fish species traits on fish reproductive success. Species traits included spawning duration, reproductive strategy, egg incubation rate, swimming locomotion morphology, general habitat preference, and food habits. Model selection results indicated that young-of-year fish density was positively related to short-term high flows during the spawning period and negatively related to flow variability during the rearing period. However, the effect of the flow regime components varied substantially among species, but was related to species traits. The effect of short-term high flows on the reproductive success was lower for species that broadcast their eggs during spawning. Species with cruiser swimming locomotion morphologies (e.g., Micropterus) also were more vulnerable to variable flows during the rearing period. Our models provide insight into the conditions and timing of flows that influence the reproductive success of warmwater stream fishes and may guide decisions related to stream regulation and management.

The use by bats of habitat features in mixed farmland in Scotland

ABSTRACT Most previous studies of the use bats make of their foraging areas have been concerned with general habitat preferences rather than with microhabitats. The present study focuses on microhabitat preference within three landscape features: linear landscape elements, ponds and rivers. The importance of linear landscape elements to bats was investigated by placing recording stations next to treelines, and others in adjacent open spaces approximately 35 m away. Most pipistrelle (Pipistrellus pipistrellus and P. pygmaeus) bat activity was recorded next to treelines and very little over open spaces. Bats used treelines for both commuting and foraging, but flew closer to treelines when commuting than when foraging. More insects were caught, and more pipistrelle feeding attempts were recorded close to treelines than further away. The relationship between the number and type of landscape elements leading to and surrounding ponds, and the use pipistrelle and Daubenton's (Myotis daubentonii) bats make of suc...

An Adaptive Modeling Technique for Instream Fish Habitat Preference of Japanese Medaka (Oryzias Latipes)

It is widely known that habitat selections of riverine fish differ wlthin and between rivers. In our past study, the preference intensity of Japanese Medaka (Or~/zias latipes) to three environmental factors of water depth, current velocity and cover ratio was quantified on laboratory open-channel experiments for developing a general habitat preference model. A simplified fuzzy reasoning method was introduced in consideration of essential vagueness of fish behaviors. The fuzzy preference intensity model was then optimally searched with a simple genetic algorithm and was successfully verified by both laboratory water tank experiments and on-the-spot examination. The results indicated that this general model showed agreement between predicted and observed spatial distribution of target fish, but the habitat preference models are still desired to be developed through field studies. In this study, we propose an adaptive modeling technique for instream fish habitat preference by conjugating the fish preference intensity model developed in laboratory experiments. The adaptive prediction model was also deterrnined by simple genetic algorithm, which enabled us to model the habitat preference of instream resident fish even with insufficient data.