The American kestrel (Falco sparverius) population of both Harrison and Washington Townships, Delaware County, east-central Indiana, showed a decline from December, 1985 to March, 1986, stabilization, and then a rise in June and July, 1986. Surveys reflect a larger kestrel population in Harrison than in Washington Township. Sex ratios from December to July indicate a greater number of males than females in both townships. Pasture was the preferred habitat of both male and female birds. No correlation was found between numbers of kestrels sighted and weather conditions. Kestrels occupied two of six nest boxes in the area and fledged a total of ten young. U. S. Fish and Wildlife Service data on 1,617 banded kestrels were analyzed. The independent effect of banding flyway on average distance traveled between banding and recovery was not significant. The independent effect of latitude was significant for the total study population of 1,617 kestrels but was not significant for a subsample of 213 birds which exhibited true migratory movement. Sex had no effect on distance traveled. The interaction of banding flyway and latitude on distance traveled was highly significant.

This thesis investigates the ecological determinants of chewing louse (Insecta: Phthiraptera) host-specificity on four species of Malaysian swiftlets (Aves: Apodidae). Influences of host coloniality on louse ecology were also demonstrated, illustrating the dependence which these permanent ectoparasites have on their hosts. Louse collections were made to look for incidences of host-specific lice occurring on the "wrong" host ("straggling"). Straggling was observed, implying that lice disperse among host species. Thus, opportunity for louse dispersal (or lack thereof) does not govern the host-specificity of chewing lice on swiftlets. Experimental transfers of lice between hosts were conducted. Louse survival was reduced on foreign host species. This implies adaptation to specific host characters, suggesting that specialisation governs chewing louse host-specificity on swiftlets. There was no evidence for reciprocal adaptation of swiftlets to their normal louse species. Lice had no impact on the fitness of either swiftlets or the related common swift. Furthermore, neither swiftlet nor swift lice were transmitting pathogenic endoparasites. This implies that chewing lice and Malaysian swiftlets have not "coevolved". Survival of transferred lice was determined by the relatedness of donor and recipient hosts. Closer related swiftlet species are more similar in body size and feather dimensions. When the feather dimensions of the microhabitat distributions of the same louse species on different hosts were compared the results suggested that lice keep the dimensions of barb and barbule diameter, at which they occur, "constant" through microhabitat shifts. This suggests that feather dimensions are the host characters which determine the survival (and host-specificity) of chewing lice on birds. The ability of chewing lice to survive on hosts with similar feather morphology implies that "host-switching", between distantly related hosts with similar morphological characters (due to parallel or convergent host evolution), may have been an important factor in the evolution of bird-louse associations.

1. The ALD and PLD muscles from the chicken.were studied throughout ex ovo development from 3 days of age until early adulthood. These two muscles provided a model for studying phasic fast fibres and tonic slow fibres. 2. Development over the first 30 days was compared in control groups and groups immobilised in two positions, "resting" and shortened. Analysis included histochemically staining for Myosin ATPase, Phosphorylase, Succinic Dehydrogenase and histological staining for nuclei/cytoplasm and nerve endings. The ALD was shown to have 2 tonic fibre types described by both contractile and metabolic enzyme markers. The PLD was shown to have different fibre types when stained for phosphorylase activity. These types were not observed with the traditional Myosin ATPase stain. The PLD also exhibited a few, p9ssibly foetal fibres during the first two weeks of ex ovo growth. Immobilisation in both positions caused the histochemically displayed activities of these enzymes to become reduced. 3. Biochemically assays for Mg 2+-activated myofibrillar ATPase (both a alone and total activity a+ b) activity were developed for chicken muscle. These assays were used to study the changes in the ALD and PLD muscles across development and with immobilisation in both positions. Both enzymes’ activities increased during normal development with peaks in activity shown at 15 days. The PLD was shown to have 4 times the Mg2+-activated myofibrillar ATPase activity than the ALD at 51 days age. For the same age, total phosphorylase activity was 3 times higher in the PLD muscles than the ALD muscles. The higher activities 161 exhibited by the fast-phasic PLD muscle over the slow-tonic ALD muscle is in agreement with the theory that the PLD-is a faster contracting, highly anaerobic, muscle and. the ALD a slow-contracting) aerobic muscle. Immobilisation in both positions showed an initial reduction in both enzyme's activities followed by a recovery despite longer periods of immobilisation. The growth peaks exhibited by these enzymes appeared to be displaced in time when inactivity through immobilisation was imposed. 4. Chickens were thyroidectomized from 6 weeks age for 4 weeks and the ALD, PLD and ST muscles were analysed for Mg 2+ -activated myofibrillar ATPase and phosphorylase (a and a+ b) activity. Sham-operated birds acted as controls. The muscles were also stained histochemically for Myosin ATPase and phosphorylase. Thyroidectomy caused a differential effect in the PLD and ST with the ALD in terms of changes in these enzymes, activities. The PLD and ST showed a significant reduction in activity of both main enzymes (phosphorylase a activity was unchanged). The ALD however, exhibited no change in activity of the two main enzymes. In conclusion the reduced presence of thyroid hormone slows down fastphasic chicken muscles but has little effect on slow-tonic chicken muscles. 5. A study was made on. the pCa-tension relationship for skinned single fibres from the ALD and PLD muscles from 9 week old chickens. The threshold for calcium activation of contraction was found to at a pCa-of 7.5 for the ALD and of 6.63 for the PLD. The ALD showed a minimum calcium binding site number of 2 and the PLD of 3. The maximum isometric tension observed was approximately 8.3 Nom- 2 for 162 both muscles. The ALD-therefore will contract at extremely low free calcium levels whereas the PLD needs almost 0.2 micro M higher free calcium to contract. Possible explanations for this difference and the differences in physiology and. function of the two muscles are presented.

From 1993-95, the behavioural ecology of the lapwing Vanellus vanellus L. was studied in Upper Teesdale, Co. Durham, with the aim of describing the behavioural mechanisms underlying some population characteristics. Significant effects of age and individuals were found in many aspects of Lapwing breeding biology. Older Lapwings returned to the breeding grounds before yearlings, with adult males returning earliest of all. First breeding attempts occurred at one-year-old for most females, but at two-years-old for most males. Males two-years-old and over showed a remarkable degree of consistency in breeding status (breeding or non-breeding) in consecutive years, even where this meant persistent non-breeding. The age of first breeding, and consistency of breeding status among males, indicates intense intermale competition for limited breeding habitat, with some males, perhaps of low quality, apparently permanently prevented from breeding. However, few differences in annual breeding success were found among females of different ages. With the exception of egg size in first clutches, where yearling females laid eggs around 5% smaller than adults, yearling and adult females were similarly fecund. Laying dates and egg volumes in first clutches exhibited high indices of repeatability between years, probably reflecting a high degree of heritability of these traits. High frequencies of polygyny were recorded, despite the traditional view of strict monogamy for this species. The mating success of male Lapwings increased between one and three years-of-age. The distinct parental roles of the sexes facilitated the occurrence of polygyny by reducing activity-budget costs of polygynous associations for both sexes. Polyterritoriality, polyandry and double-brooding were also recorded and discussed.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.