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On a Dhole Trail: Examining Ecological and Anthropogenic Correlates of Dhole Habitat Occupancy in the Western Ghats of India  [PDF]
Arjun Srivathsa, Krithi K. Karanth, Devcharan Jathanna, N. Samba Kumar, K. Ullas Karanth
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0098803
Abstract: Although they play a critical role in shaping ecological communities, many threatened predator species are data-deficient. The Dhole Cuon alpinus is one such rare canid with a global population thought to be <2500 wild individuals. We assessed habitat occupancy patterns of dholes in the Western Ghats of Karnataka, India, to understand ecological and anthropogenic determinants of their distribution and habitat-use. We conducted spatially replicated detection/non-detection surveys of dhole signs along forest trails at two appropriate scales: the entire landscape and a single wildlife reserve. Landscape-scale habitat occupancy was assessed across 38,728 km2 surveying 206 grid cells of 188-km2 each. Finer scale habitat-use within 935 km2 Bandipur Reserve was studied surveying 92 grid cells of 13-km2 km each. We analyzed the resulting data of dhole signs using likelihood-based habitat occupancy models. The models explicitly addressed the problematic issue of imperfect detection of dhole signs during field surveys as well as potential spatial auto-correlation between sign detections made on adjacent trail segments. We show that traditional ‘presence versus absence’ analyses underestimated dhole habitat occupancy by 60% or 8682 km2 [na?ve = 0.27; (SE) = 0.68 (0.08)] in the landscape. Addressing imperfect sign detections by estimating detection probabilities [(L) (SE) = 0.12 (0.11)] was critical for reliable estimation. Similar underestimation occurred while estimating habitat-use probability at reserve-scale [na?ve = 0.39; (SE) = 0.71 (0.06)]. At landscape scale, relative abundance of principal ungulate prey primarily influenced dhole habitat occupancy. Habitat-use within a reserve, however, was predominantly and negatively influenced by anthropogenic disturbance. Our results are the first rigorous assessment of dhole occupancy at multiple spatial scales with potential conservation value. The approach used in this study has potential utility for cost-effectively assessing spatial distribution and habitat-use in other species, landscapes and reserves.
Sarcocystosis of chital-dhole: conditions for evolutionary stability of a predator parasite mutualism
Maithili M Jog, Milind G Watve
BMC Ecology , 2005, DOI: 10.1186/1472-6785-5-3
Abstract: A tolerant predator strategy and a low or moderately virulent parasite strategy which together constitute mutualism are stable only at a high frequency of recycling of parasite and a substantial prey – capture benefit to the predator. Unlike the preliminary expectation, parasite will not evolve towards reduced virulence, but reach an optimum moderate level of virulence.The available data on the behavioral ecology of dhole and chital suggest that they are likely to meet the stability criteria and therefore a predator-parasite mutualism can be stable in this system. The model also points out the gaps in the current data and could help directing further empirical work.Preferential killing of sick and disabled prey individuals by the predator has been the focus of many ecologists working with different predator – prey systems. In a variety of prey predator systems, diseased or weaker animals are shown to be consumed in greater proportion by predators [1-5]. Increased susceptibility of parasitized prey to predation, or predator preference for parasitized prey is possible under a set of conditions [6-8]. Where the prey species is an intermediate host and the predator is the definitive host for a parasite species, the capture of prey is often an essential part of the life cycle. Therefore any mechanism that makes the prey susceptible to predation would enhance the parasite fitness. In such relationships the susceptibility induced by the parasite can be very specific towards the predator host [9]. A mutualistic relationship can be said to exist between a predator and a parasite [10] if the cost of harboring the parasite is less than the benefit of greater success in catching the prey [1]. Some evidence suggestive of predator-parasite mutualism comes from dhole or Indian wild dog (Cuon alpinus) and a protozoan parasite (Sarcosystis axicuonis) with chital or spotted deer (Axis axis) as the prey-host [1,11].There can be a potential problem in such a mutualistic relationship. L
The Pack Hunter (Dhole): Received Little Scientific Attention  [PDF]
Ambika Pd Khatiwada,KD Awasthi,Narayan Pd Gautam,Shant Raj Jnawali,Naresh Subedi,Achyut Aryal
The Initiation , 2011, DOI: 10.3126/init.v4i0.5531
Abstract: The dholes received little scientific attention due to the lower charisma factor than other larger carnivores found in the same areas like Tiger and Snow Leopard. This is the first study of dholes that was conducted in Kanchenjunga Conservation Area (KCA), Nepal in 2010. Camera trapping, sign survey, interview and group discussion with local people were carried out to assess the presence/absence of dholes in KCA, conflict with humans and to know the history of dholes in the area. The camera trapping evidence (Three pictures of dholes caught on camera trap) confirmed the dhole presence in KCA. According to the Snow Leopard Conservation Sub-Committee (SLCC) report about 87.5% of livestock were killed by dholes only in Yamphudin. Conservation education and comprehensive carnivore conservation action plan is recommended for the conservation of dholes. DOI: http://dx.doi.org/10.3126/init.v4i0.5531 The Initiation Vol.4 2011 8-13
Cortinarius alpinus as an example for morphological and phylogenetic species concepts in ectomycorrhizal fungi
U. Peintner
Sommerfeltia , 2008, DOI: 10.2478/v10208-011-0009-1
Abstract: Extensive morphological and molecular analyses of closely related species from alpine, subalpine and montane habitats should enable a comparison of ecological, morphological and phylogenetic species concepts in ectomycorrhizal mushrooms. One fundamental question of this study was whether alpine species really exist, and which criteria, besides the specific habitat, could reliably be used for the de-limitation of such taxa. For this reason, 56 rDNA ITS sequences were generated or downloaded from GenBank for 10 closely related species of Cortinarius subgenus Myxacium, section Myxacium. Several collections were sequenced for each of the following taxa: Cortinarius absarokensis, C. alpinus, C. favrei, C. fennoscandicus, C. grallipes, C. mucosus, C. muscigenus, C. septentrionalis, C. trivialis and C. vernicosus. Moreover, spore statistics were carried out for 38 collections of alpine and subalpine taxa. These data provide clear evidence for C. favrei being a synonym of C. alpinus. C. absarokensis and C. alpinus can clearly be delimited based on pileus diameter and average dry weight per basidiome, even in overlapping habitats, but spore size and shape is not a good distinguishing character. Phylograms have very short branches, and base differences between ITS sequences are generally very low in this group, and give no resolution for the included taxa of this section. Based on these results, species concepts of ectomycorrhizal mushrooms are discussed in detail.
New report of Sorex alpinus Schinz, 1837 (Mammalia: Insectivora) from Piatra Craiului Mountains (Romania)
Ioana Nae
Travaux de l'Institut de Speologie Emile Racovitza , 2010,
Abstract: The distribution of the alpine shrew in Romania has alot of gaps because of the small sized populations that remained in the alpine regions and their dinamics. Acording to lierature, Sorex alpinus is present in small populations in the Eastern and Southern Carpathians. This faunal note contribute to a better understanding of local distribution and habitat preferences of populations of Sorex alpinus from the Romanian Carpathians.
Plecotus alpinus: primi dati sull'utilizzo dell'habitat
Adriano Martinoli,Damiano Preatoni,Roberta Chirichella,Sabrina Mattiroli
Hystrix : the Italian Journal of Mammalogy , 2003, DOI: 10.4404/hystrix-14.0-4275
Abstract: Negli ultimi anni il numero delle specie di Chirotteri note per l?Europa si è accresciuto, grazie all?uso di tecniche di genetica molecolare, ed in particolare il genere Plecotus è quello che ha registrato maggiori cambiamenti con la descrizione di tre nuove specie: Plecotus kolombatovici, P. alpinus e P. sardus (Kiefer & Veith, 2001; Mucedda et al., 2002). Alla luce di queste nuove scoperte, la distribuzione geografica e le preferenze dell?habitat delle due specie ?storiche? di Orecchione in Europa, Plecotus auritus e P. austriacus, dovrebbero essere riviste: in questo contesto si inserisce l?indagine svolta nel Parco Regionale Campo dei Fiori (in provincia di Varese) sulla prima colonia riproduttiva di Plecotus alpinus segnalata per la regione Lombardia. Al fine di valutare le preferenze nell?uso dell?habitat e le direttrici di spostamento preferenziali di tale specie, nonché per l?identificazione di siti di rilevanza per l?allevamento della prole, si è fatto ricorso a tecniche di radiolocalizzazione, subordinate alla cattura a vivo degli animali. Le catture si sono svolte nel periodo 15 giugno ? 15 agosto del 2002 e del 2003. Per ogni individuo catturato, oltre alla determinazione di specie, sesso e classe d?età, sono stati rilevati i dati biometrici e prelevati campioni di tessuto destinati all?analisi genetica. Sono state inoltre registrate le emissioni ultrasonore. Durante il primo anno di indagine sono state seguite mediante radiolocalizzazione 5 femmine adulte (4 allattanti ed una non allattante) e due femmine subadulte, mentre durante il secondo anno sono state munite di radiocollare 6 femmine adulte (5 allattanti ed una non allattante) ed una femmina subadulta. Ai pipistrelli è stato applicato un emettitore radio (tag modello LB-2, Holohil Systems Ltd, Ontario, Canada). Il segnale emesso è stato ricevuto in campo mediante l?utilizzo di radio (Wildlife Materials, Inc.) connesse ad antenne Yagi a tre elementi. Ogni animale è stato seguito a partire dall?uscita dal roost fino al definitivo rientro all?alba del giorno successivo, per tutto il periodo in cui il tag risultava attivo (7-10 giorni) e ne è stata rilevata la posizione almeno ogni quindici minuti. I dati ottenuti sono stati integrati su Sistema Informativo Territoriale (GIS) ARC/INFO 8.2 al fine di poter procedere all?elaborazione dei dati di localizzazione per l?analisi dei domini vitali e la definizione dei corridoi di spostamento e delle principali aree di foraggiamento. Dai dati ottenuti è risultato che la maggior parte degli individui indagati utilizza più di un sito di foraggiament
Inter-annual growth of Arctic charr (Salvelinus alpinus, L.) in relation to climate variation
David M Kristensen, Thomas R J?rgensen, Rasmus K Larsen, Mads C Forchhammer, Kirsten S Christoffersen
BMC Ecology , 2006, DOI: 10.1186/1472-6785-6-10
Abstract: Inter-annual growth of the circumpolar Arctic charr (Salvelinus alpinus, L.) was analysed in relation to climatic changes observed in the Arctic during the last two decades. Arctic charr were sampled from six locations at Qeqertarsuaq in West Greenland, where climate data have been recorded since 1990. Two fish populations met the criteria of homogeny and, consequently, only these were used in further analyses. The results demonstrate a complex coupling between annual growth rates and fluctuations in annual mean temperatures and precipitation. Significant changes in temporal patterns of growth were observed between cohorts of 1990 and 2004.Differences in pattern of growth appear to be a consequence of climatic changes over the last two decades and we thereby conclude that climatic affects short term and inter-annual growth as well as influencing long term shifts in age-specific growth patterns in population of Arctic charr.The number of Arctic charr (Salvelinus alpinus, L.) phenotypes varies considerably within and across localities on Disko Island off the west coast of Greenland [1,2]. Two landlocked populations have been described here as well as dimorphic populations with an anadromous morph and a resident morph in rivers [1,2], but whether the two morphs are reproductively isolated remain unclear. The resident and landlocked populations are isolated in the same locality throughout their entire life cycle, thereby presenting an excellent opportunity to investigate differential effects of abiotic factors on somatic growth.Fish are ectotherms and hence rely exclusively on external sources of heat. Metabolic produced heat is rapidly lost through the gills and the epidermis and consequently body temperature fluctuates closely with changes in the ambient water temperature [3]. Indeed, since the metabolic processes within the animals are strongly temperature dependent [4], ambient water temperature exerts a major influence on all physiological and behavioural processes
The Alpine Long-Eared Bat (Plecotus alpinus Kiefer and Veith, 2001) is present also in Piedmont Region: first record revealed by DNA analysis
Ilaria Trizio,Elena Patriarca,Paolo Debernardi,Damiano Preatoni
Hystrix : the Italian Journal of Mammalogy , 2003, DOI: 10.4404/hystrix-14.1-2-4321
Abstract: Riassunto L'orecchione alpino (Plecotus alpinus Kiefer e Veith, 2001) è presente anche in Piemonte: prima segnalazione accertata mediante analisi del DNA Viene riportata la prima segnalazione per il Piemonte della specie Plecotus alpinus (Kiefer e Veith, 2001) recentemente descritta. Per l'esatta determinazione specifica si è fatto ricorso a tecniche genetiche, in quanto non sono state ancora messe a punto tecniche discriminanti basate su parametri biometrici. La presenza di questa nuova specie anche in Piemonte dovrebbe indurre ad un monitoraggio su larga scala, per definirne in dettaglio la distribuzione e le preferenze di habitat, finalizzate anche alla determinazione dello status delle popolazioni presenti.
Differentiation at the MHCIIα and Cath2 Loci in Sympatric Salvelinus alpinus Resource Morphs in Lake Thingvallavatn  [PDF]
Kalina H. Kapralova, Johannes Gudbrandsson, Sigrun Reynisdottir, Cristina B. Santos, Vanessa C. Baltanás, Valerie H. Maier, Sigurdur S. Snorrason, Arnar Palsson
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069402
Abstract: Northern freshwater fish may be suitable for the genetic dissection of ecological traits because they invaded new habitats after the last ice age (~10.000 years ago). Arctic charr (Salvelinus alpinus) colonizing streams and lakes in Iceland gave rise to multiple populations of small benthic morphotypes, often in sympatry with a pelagic morphotype. Earlier studies have revealed significant, but subtle, genetic differentiation between the three most common morphs in Lake Thingvallavatn. We conducted a population genetic screen on four immunological candidate genes Cathelicidin 2 (Cath2), Hepcidin (Hamp), Liver expressed antimicrobial peptide 2a (Leap-2a), and Major Histocompatibility Complex IIα (MHCIIα) and a mitochondrial marker (D-loop) among the three most common Lake Thingvallavatn charr morphs. Significant differences in allele frequencies were found between morphs at the Cath2 and MHCIIα loci. No such signal was detected in the D-loop nor in the other two immunological genes. In Cath2 the small benthic morph deviated from the other two (FST = 0.13), one of the substitutions detected constituting an amino acid replacement polymorphism in the antimicrobial peptide. A more striking difference was found in the MHCIIα. Two haplotypes were very common in the lake, and their frequency differed greatly between the morphotypes (from 22% to 93.5%, FST = 0.67). We then expanded our study by surveying the variation in Cath2 and MHCIIα in 9 Arctic charr populations from around Iceland. The populations varied greatly in terms of allele frequencies at Cath2, but the variation did not correlate with morphotype. At the MHCIIα locus, the variation was nearly identical to the variation in the two benthic morphs of Lake Thingvallavatn. The results are consistent with a scenario where parts of the immune systems have diverged substantially among Arctic charr populations in Iceland, after colonizing the island ~10.000 years ago.
Effect of Water Velocity on the Timing of Skeletogenesis in the Arctic Charr, Salvelinus alpinus (Salmoniformes: Teleostei): An Empirical Case of Developmental Plasticity  [PDF]
Richard Cloutier,Alain Caron,Thomas Grünbaum,Nathalie R. Le Fran?ois
International Journal of Zoology , 2010, DOI: 10.1155/2010/470546
Abstract: Phenotypic plasticity has been demonstrated in fishes but rarely addressed with respect to skeletogenesis. The influence of water velocity on the sequence of chondrification and ossification is studied for the median fins of Arctic charr, Salvelinus alpinus, during a period of 90 days post hatching. Time of appearance, relative position within sequences, and direction of development among serially repeated elements are compared between two velocity treatments. Water velocity has induced changes in the timing of events and to a lesser extent on the relative sequence events in the locomotor system. Ossification is more responsive to water velocity than chondrification, and early-forming elements are less responding than late-forming elements. Directions of development are fairly conservative. It is suggested that a faster sustained swimming (behavioural adaptation to a higher water velocity) could induce differential mechanical stresses on developing skeletal elements involved in locomotion and therefore induce changes primarily in the timing of the ossification. 1. Introduction Developmental sequences are known to be controlled genetically as well as constrained environmentally [1, 2]. A specific type of developmental sequence, the sequences of chondrification and ossification, has been investigated in a large diversity of fishes [3–13], amphibians [14–19], reptiles (including birds) [20–28], and mammals [29–32]; both sequences refer to the specific ontogenetic order in which anatomical cartilaginous and bony structures appear during the early development of vertebrates. Information derived from such sequences could be used to validate homology [12, 13, 33] and phylogenetic position [14, 20], and to infer evolutionary developmental patterns and processes (e.g., heterochrony) [11, 29, 30, 32, 34, 35]. It has been suggested that ossification sequences conform to functional needs [29–31, 35, 36]. In a general way, structures that are required functionally earlier during development will ossify earlier in the sequence although inconsistencies may occur [3, 37, 38]. Among the functional requirements most influential on the ossification, locomotion has been shown to induce differential mechanical stress, which may change the shape, size, or toughness of the bones [39–42]. In order to understand if the observed patterns of ossification are the result of processes controlled genetically or developmentally, as well as a response to environmental constraints, experimental studies on living fish morphology are of primary interest. The effects of many environmental
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