A fine-grained analysis of a Monk parakeet (Myiopsitta monachus) nest suggests a nonhomogeneous internal structure

We report first data on the fine-grained structure (branch diameter, length and diversity) in three different sectors [core (central side), buffer (peripheral side), and nest chamber)] of a nest of Monk Parakeets (Myiopsitta monachus) from a non-native breeding site located in an urban park (Rome, central Italy). The central core sector was characterized by longer and thicker branches capable of supporting the nest. The peripheral part (buffer) was characterized by less long and less thick branches with the function of completing the structure. Branches building the nest chamber were shorter and less thick but very diversified in size, because they included both small branches supplied inside the chamber and longer branches covering it. This diversification of the internal chamber (nest chamber) could be functional to maintain stable temperatures of incubator chambers compared to large fluctuations outside the nest. The presence of leaves of herbaceous species (Hordeum leporinum) could play a bactericidal role for the nest plant material.

The nest of the Hastings River mouse Pseudomys oralis.

THE most detailed information on the burrows and nests of Australian small mammals are reported by Watts and Aslin (1981). The nests of several species of Pseudomys have been described and vary between species. Three nests of the New Holland mouse Pseudomys novaehollandiae were excavated from sand burrows and described as being partially comprised of Eucalypt leaves (Kemper 1981). In South Australia, silky mice P. apodemoides construct nests of shredded bark within a nest chamber of approximately 15 cm (Watts and Aslin 1981). The desert mouse P. desertor reputedly builds dry grass nests in shallow constructions (Read et al.1999) and the long-tailed mouse P. higginsi and eastern chestnut mouse P. gracilicaudatus, delicate mouse P. delicatulus and Gould?s mouse P. gouldii all construct nests of plant material (Watts and Aslin 1981; Green 1993; Fox 1995) mostly grass. The nests of the smokey mouse P. fumeus are constructed of dried grass and Allocasuarina needles that are shaped in a cup form (10-15cm in diameter) (Woods and Ford 2000).

Influence of the semiaquatic habit in determining burrow structure of the star-nosed mole (Condylura cristata)

Condylura cristata is unique from most talpids in being semiaquatic. This report investigates the effect of a water habitat on burrow structure and is the first description of completely excavated burrow systems of the star-nosed mole, representing reedbed and lakeside habitats. Major features of the burrow structure included lack of surface ridges and mounds, unplugged burrows, along the edge of water, lack of steep vertical shafts to lower levels, deep tunnels not confined to particular areas of burrow system, a single active nest chamber containing dead leaves and freshly chewed pieces of Typha, and absence of special chambers for food storage or defecation. In comparing the influence of aquatic habits on structure of the burrow with terrestrial (Scalopus aquaticus) and aquatic (Desmana moschata) species of Talpidae, the semiaquatic Condylura is intermediate in position.

Behavioural aspects of the ecology of the sand martin flea Ceratophyllus styx jordani Smit (Siphonaptera)

The behaviour of the sand martin flea Ceratophyllus styx jordani Smit was studied in relation to its ecology.The cocooned resting imago in the host's old nest is the main over-wintering stage. Mechanical disturbance of the cocoons by the exploratory habits of the newly returned sand martins elicits emergence of the imagines in spring. The seasonal rise in temperature is not, by itself, important in causing emergence, as it does not become effective until many weeks after the martins have returned, by which time undisturbed fleas are likely to have died inside their cocoons.When the imagines break out of their cocoons they are negatively photo-tactic, but become positively phototactic within 24 h. This response takes them outwards along the martin's disused burrow until the increasing intensity of light reduces their activity so that they aggregate on the lower lip of the entrance. Positive phototaxis prevents them dispersing downwards from the entrance.Periodically the fleas bury themselves in sand; this response may function for water conservation. The proportion buried is greatest at night.The sand martin's habit of hovering close to a succession of entrances renders it accessible to the fleas, whose main host-finding response is an outward jump from the burrow entrance. This jump is released by a sudden decrease in light intensity and is directed towards dark objects. Vibration and air currents do not release jumping.Dispersal from aggregations in disused burrows may occur by transport on the host, or by spontaneous horizontal emigration along the cliff face, or by falling after an unsuccessful host-finding jump. Fleas which have fallen become negatively geotactic and positively anemotactic. Fleas wandering on the cliff face visually detect burrow entrances up to 30 cm away, and turn towards them. Preference for moister sand and, possibly, a negative phototactic response, may induce the fleas to remain in newly found burrows.Small aggregations of fleas also occur at the entrances of burrows currently in use by martins. Fleas circulate between the entrance and nest chamber of these burrows, until the martin begins to incubate its eggs. The entrance aggregation then disappears and fleas accumulate in the nest chamber. There is some interchange of fleas between infested burrows in the martin's pre-incubation period.The general pattern of behaviour resembles that of C. gallinae. Behavioural differences between the two species are related to the ecology of their hosts. C. styx is adapted to dispersal and host finding in its host's breeding site, whereas C. gallinae is adapted to reach foraging birds. This difference partly accounts for the narrow host specificity of C. styx and the wide host range of C. gallinae.My grateful thanks are due to Chris. Mead and Giles Pepler for information on sand martins' behaviour and migratory arrival. I would also like to thank Brian Little, who introduced me to several colonies in the Tyne Valley. The valuable advice of the Hon. Miriam Rothschild and Dr E. T. Burtt is especially acknowledged.