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| Carattere & la crescita del cucciolo Come relazionarsi con un cucciolo, problemi più comuni, come risolverli... |
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Nagi e Ishta e Panuhsè
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lo so Topo, vuoi uccidermi..
questa è una paginetta semplice..(ma mica vorrai anche che la traduca no?..già ho dovuto lavorare per metterla..) ![]() tratto da: Conservation and control strategies for the wolf (Canis lupus) in western Europe based on demographic models Guillaume Chapron a,∗, Stéphane Legendre a, Régis Ferrière a,b, Jean Clobert c, Robert G. Haight da Laboratoire d’écologie, CNRS UMR 7625, École normale supérieure, 46, rue d’Ulm, 75230 Paris cedex 05, France b Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA c Laboratoire d’écologie, CNRS UMR 7625, bât. A, 7e étage, université Pierre-et-Marie-Curie, case 237, 7, quai Saint-Bernard, 75252 Paris cedex 05, France d USDA Forest Service, North Central Research Station, 1992 Folwell Ave., St. Paul, MN 55108, USA .....The unit of a wolf population is the pack, consisting of a breeding pair and their offspring (from one or more generations [25,26]). The dominant adult female in each pack breeds every year, usually producing a single litter. Subordinates rarely become dominant in their natal pack [27]. Pups reach their adult size by winter, and most of them disperse as yearlings [28–30]. A dispersing wolf may colonize a vacant territory, or it may join another pack and replace a missing breeding member [29,31–33]. When both breeding adults die, the pack usually disintegrates, leaving the territory vacant and creating an opportunity for recolonization [33].Wolves are not habitat-specific and can live wherever they have sufficient food resources and are tolerated by humans [7,34]. There is no simple relationship between human density and wolf persistence in a given area [35]. For example, in the Abruzzi region, in Italy, wolves survive alongside 29 people/km2, whereas they have been exterminated amongst 1.33 people/km2 in Sweden [36]. 2.2. Life cycle modelling Our models are based on the wolf life cycle described in previous individual-based model papers [37,38] and refined with the few available demographic data on European wolves [12,39]. The population is divided into several stages defined by age and breeding status. The algorithms allow an individualbased approach.Wolves present in packs are pups (0– 6 months), juveniles (6–18 months), subadults (18– 30 months), adults (> 30 months) and pack leaders that are at least 18 months old. Wolves outside packs are juveniles that have dispersed from their packs and stay one year as lonely wolves since they are too young to reproduce. All our population projections involve the same sequence of events. (i) Winter mortality affects the whole population and accounts for annual mortality. (ii) Dispersal of subordinates is conditional to the survival of the breeding pair: if the breeding pair disappears (both partners die), remaining pack members disperse, but if at least one breeder survives, subordinates disperse with some probability specific to their class. (iii) Dispersing wolves search for a vacant territory and a partner. We neglect the probability that a dispersing wolf joins an extant pack where no breeder is missing. (iv) Reproduction takes place in spring if a breeding pair is present. Age at first reproduction is always 22 months (dispersing juveniles must wait one year before looking for a mate). Only one litter is produced per year. (v) Pup mortality takes place in summer and accounts for infectious diseases that are often deadly for pups. In autumn, the distribution of wolves in the population is censused and then updated according to the following scheme (see also Fig. 1). ![]() Fig. 1. Life cycle graph for a wolf stage-structured population. P: Pups, J: Juveniles, S: Subadults, Di: Dispersers, A: Adults, Do: Dominants. All stages are in packs except dispersers. See text for arrow details. Stiamo battendo il record dell'OT....
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Ciao! Andrea Loredana Jacopo e Nagi & Ishta & Panuhsè & Tawoka & Aluhksis & Awonn ![]() "... io sono un principe libero e ho altrettanta autorità di fare guerra al mondo intero quanto colui che ha cento navi in mare..." Black Samuel Bellamy, Pirata |
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