BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.
Niche conservatism is the tendency of related species to retain ancestral tolerances after geographic separation. We used Ecological Niche Modelling and Principal Components Analysis of bioclimatic and habitat variables to describe the extent of the species niche, and degrees of bioclimatichabitat niche conservatism within the mountain hare (L. timidus) clade. Mountain hare niche space was contrasted with that of the European hare (L. europaeus), to shed light on species interactions in contact zones throughout Europe. All five subspecies of mountain hare had quantifiably distinct niches. Fennoscandian (L.t. sylvaticus, L.t. timidus) and highland (L.t. scoticus, L.t. varronis) subspecies, however, were most similar, exhibiting greatest apparent niche conservatism. They inhabit tundra, boreal forest and uplands, and, hence are presumed most similar to the ancestral form. The Irish hare was distinct, being consistently distinguished from other mountain hares in both 2D and nth dimensional (4D) niche space. The ecological distinctiveness of the Irish hare provides further evidence that it is an Evolutionarily Significant Unit, particularly vulnerable to Electronic supplementary material The online version of this article
The method used most extensively in Europe to prevent damage due to browsing of woody plants consists of shelter pipes made of plastic material or net. This system, however, is not practical for plants such as olive trees where it is desirable for the branches to develop more than the trunk. For this reason, in an area with a high deer (Dama dama) population, three liquid repellents were tested for their ability to prevent damage by cervids to olive seedlings (Olea europaea). Tree Guard and Eutrofit reduced the percentage of plants browsed with respect to the control by a statistically significant extent through the third week (54.5 and 40.9% reduction, respectively), while for Hot Sauce, the differences did not reach significance after the first week. Tree Guard and Eutrofit were also able to reduce the level of damage for the entire eight week period of the test, while Hot Sauce did not differ from the control in a statistically significant manner. The use of repellent substances such as Tree Guard and Eutrofit to reduce the damage caused by cervids to olive groves therefore seems a possible strategy under conditions of medium and low density of animals. Eutrofit was the most economical product from the point of view of cost effectiveness.
In Tuscany, the red-legged partridge (Alectoris rufa) became extinct at the beginning of the 20th century. Recently, some attempts have been made to re-establish wild populations in Tuscany using farm reared birds, but in most cases the released populations have shown difficulties in reaching sufficient viability, even in areas where the habitat can be considered suitable. Modern technologies for rearing game-birds may be not suitable for reintroduction purposes. For this reason we carried out preliminary research to evaluate the survival of red legged partridges reared under natural condition (Natural) compared to those farm reared (Artificial). Natural rearing occurred in a large pen where birds were allowed to mate freely and to nest. Natural reared birds reached a larger size than artificially-reared birds. Partridges were released in a 7.56 sq km protected area located in the province of Leghorn (western Tuscany, Italy). We followed the fate of 22 young radio-tagged red-legged female partridges (half Natural and half Artificial) and 56 young red-legged partridges (25 Artificial and 31 Natural) marked with different coloured ponchos. The survival of Natural radio-tagged red-legged partridges was double that of the Artificial red-legged partridges. After six months, the re-sighting rate of the Natural poncho-marked birds reached 22.6% whereas none of the Artificial stock was re-sighted. The preliminary results of this research suggest that Natural rearing may be an important tool to improve the success of partridge reintroduction
BIANCIFIORI, Bucciarelli, Santilli and Ribacchi (1963) described the occurrence of pulmonary adenomas and carcinomas in CBA/Cb/Se male and female mice treated with large doses of isoniazid or equimolar doses of hydrazine sulphate. The CBA strain was found by Orr (1947) to be the most resistant to the induction of pulmonary tumours of 6 strains tested with intranasal methylcholanthrene. However, tumour incidence was only slightly less in CBA/Cb/Se mice than in BALB/c/Cb/Se mice treated with large doses of isoniazid or hydrazine sulphate (Biancifiori and Ribacchi, 1962). In addition to the pulmonary tumours, hepatomas occurred in the same CBA mice and these are described here.When it had been shown that it was possible to induce pulmonary tumours in BALB/c and CBA mice with both isoniazid and hydrazine and liver tumours in CBA mice with hydrazine, it was thought interesting to attempt to promote skin tumours by croton oil following initiation with the one or the other compound. The BALB/c strain was chosen for this experiment. MATERIAL AND METHODSThe following solutions were prepared: 2 per cent aqueous isoniazid, 1 13 per cent aqueous hydrazine sulphate (i.e. equimolar with the isoniazid) and 1-30 per cent aqueous iso-nicotinic acid. Croton oil was 0 5 per cent in acetone. All the chemicals were pure and supplied by Farmitalia, Milan. Isoniazid, hydrazine sulphate and iso-nicotinic acid were given by stomach tube daily in a dose of 0-1 ml. per mouse and croton oil in a dose of 0 3 ml. which was painted twice weekly on the skin of the back after shaving with an electric clipper.Experiment I.-The mice were of the CBA/Cb/Se strain maintained in Perugia and the chemicals were given in aqueous solution by stomach tube daily for 36 weeks starting at 8 weeks of age as described by Biancifiori et al. (1963).Experiment II.-The mice were of the BALB/c/Cb/Se strain maintained in Perugia under the same conditions as in Experiment I.Treatment was started at 8 weeks of age and consisted of oral administration of isoniazid or hydrazine for 4 weeks, followed by croton oil for 30 weeks.
This study investigated the effect of providing elevated perches in growing pens on the morphology and behaviour of young pheasants. Pheasants reared with perches from one week old were observed roosting off the ground significantly more frequently when moved into a pen containing trees at five weeks old than pheasants reared without perches (roosting pheasants: 24.3% vs. 6.7%; p < .01). The presence of perches reduced the level of plumage damage caused by feather pecking (damage scores: 2.3% vs. 2.1%; p < .05). Pheasants reared in huts with perching were larger overall than those from control huts, in particular were heavier (weights: 356.9 g vs. 345.2 g) and had longer and thicker tarsi than control pheasants (60.61 mm vs. 59.35 mm and 4.715-6.571 mm vs. 4.705-6.412 mm, respectively). Since roosting on tree branches is an important anti-predator behaviour, providing perches at an early stage of life in the captive rearing environment may be helpful in order to improve survival of the captive reared pheasant after release in the wild. Furthermore, the study suggests that a simple and easy husbandry technique, providing elevated perches, may improve the welfare and fitness of farm-reared game birds.
The releasing of farm-reared pheasant (Phasianus\ud colchicus) is a very common practice in order to sustain high\ud hunting pressures. However farm-reared birds may be\ud carriers of parasites and diseases for the natural populations.\ud We compared the parasite egg and oocyst prevalence and\ud abundance of excretions found in faecal droppings collected\ud in 13 different protected areas of Tuscany: seven areas where\ud farm-reared pheasants are released every year to increase the\ud reproduction and dispersion of the wild population (restocking\ud areas) and in six areas where the production of pheasants\ud is guaranteed only by the wild population (wild areas).\ud Eimeria spp. oocysts were found in 33 of 129 (25.6%)\ud samples collected in wild areas and in 59 of 119 (51.3%) of\ud samples collected in restocking areas. Nematode eggs were\ud found in 21 of 129 (16.3%) samples collected in wild areas\ud and in 59 of 119 (49.6%) of samples collected in restocking\ud areas. Significant differences were found for Capillaria spp.\ud (31.9% of restocking areas vs. 9.3% of wild areas) and\ud Syngamus spp. (10.1% of restocking areas vs. 3.1% of wild\ud areas) but not for Heterakis or Ascaridia spp. (7.6% of\ud restocking areas vs. 3.9% of wild areas). Parasitic excretion\ud abundance was higher in the droppings collected in restocking\ud areas compared to those collected in wild areas, but\ud differences were significant only for Eimeria and Capillaria\ud spp. In order to reduce the risk of spreading parasites and\ud diseases, we suggest to interpose a strip (larger than the\ud home range of the pheasants) where hunting is not forbidden\ud between the restocking areas and the wild areas, and\ud pheasant releases should not be allowed at least within a\ud “pheasant home range distance” from the wild area
Modern game birds rearing methods use mechanical incubators to hatch eggs and artificial brooders to intensively rear birds. However, the lack of parental care can have consequences on behavior and welfare of these birds affecting also survival after their release in the wild. In this study, we compared the response of 4-week-old young pheasants (brooded by a foster mother hen and artificially brooded) to two behavioral tests (duration of tonic immobility and response to aerial predator). Tonic immobility was significantly different between the two groups of birds indicating a higher level of fear in artificially brooded pheasants compared to brooded pheasants. Pheasants brooded by a foster hen showed a stronger response to aerial predator compared to artificially brooded pheasants. The foster hen seems to have a positive effect on pheasant chicks’ behavior reducing the fear and improving the ability to perceive threats.
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