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High arsenic (As) contents have been reported in numerous Cretaceous-Paleogene boundary (KPB) clays worldwide including those from Spain (at Caravaca and Agost) and N. Zealand (at Woodside Creek). The Deccan Traps (India) enormous volcanism is one of the interpretations which have been offered to explain this anomaly. This report shows that the estimated surface densities of As in the boundary clays in Spain and New Zealand strongly contradict that anomalous As was sourced by this volcanic event.
Breeding was studied in feral pigs Sus scrofa Linnaeus, 1758 inhabiting the north­ern part of the South Island, New Zealand. In a sample of 1,117 female pigs 50.4% showed evidence (pregnancy or lactation) that they were breeding. There was no statistically significant regional variation in the breeding status of females. Breeding occurred throughout the year with birth peaks in July-November and March. Among 101 females 5-8 months old, 30 (29.7%) were pregnant. The oldest breeding sow was 14 years old. Breeding females up to 17 months old were significantly heavier than non-breeding females, but the difference ceased to be significant for older ani­mals. Pregnant females averaged 6.2 foetuses (range 1 - 11). Lactating females had on average 5.4 teats extended (range 1 - 12). For areas where pigs are considered a pest species a simulation model predicted a population recovery time of 30 months from a 70% kill.
Fifty-nine fallow deer Dama dama dama (Linnaeus, 1758) fitted with radio collars were monitored in the Blue Mountains, Otago, New Zealand, between September 1985 and February 1988 to determine home range size ant! patterns of range development. Fallow deer occupy small annual ranges, averaging 66 ha for females and 189 ha for males (90% isopleths calculated by the Harmonic Mean method). For resident animals the respective values were 50 ha and 127 ha. Bimonthly seasonal range size varied with sex, age-class and season, with different seasonal patterns for males and females. Only one adult female dispersed, and most females occupied the same core range throughout the period they were monitored. Some subadult females did move into new areas, by a process of range extension rather than a single dispersive range shift. In contrast most males monitored for more than 6 months shifted their range, but the distances between successive seasonal range centres never exceeded 2,6 km and could not be reliably distinguished from adult seasonal movements. The range stability and slow dispersal rates of fallow deer should make them easier to control than the other common introduced deer species in New Zealand, and should make it practical to have different management objectives and regimes for adjacent catchments in the Blue Mountains.
Purpose. To compare the effectiveness of interviewer-led and postal surveys in gathering adequate health data for occupational health programmes among farmers. Methods. Two cross-sectional studies of farmers from southern New Zealand were conducted. Farms were randomly selected from the public land valuation roll and all farmers and farm workers invited to participate in the farmers' health study. First, 477 farms were invited to participate in an interviewer administered questionnaire and health check; and second, a further 432 farms were selected and invited to participate in a self-administered postal survey. Both groups completed the same questionnaire. Results. The response for the interviewer-led and postal surveys was 65.4% and 51.6% respectively. The 2 groups differed demographically, with fewer young farm workers in the postal survey, but were similar in all areas of health information collected, except that men in the interviewer-led survey were significantly more likely to have a psychological disturbance than men in the postal survey (chi 2 =5.06, df=1, p=0.024). Conclusions. Despite the interviewer-led survey having a higher response rate, the postal survey produced similar health data, which is adequate for planning occupational health programmes for farmers. Extra effort should be made to recruit younger farm workers in future research.
The paper discusses the changing pattern of New Zealand farm production and economic activity during the last two decades in a way that will identify implications for Poland and other countries in transition. The outline of the paper is as follows. Firstly there is a brief history of New Zealand agriculture and some description of the current situation. This is followed by a description of the significant transformation that occurred during the 1980s and 1990s. This will highlight the key issues during the period of transition and the longer term consequences. These issues form the basis of some preliminary conclusions regarding the relevance of the New Zealand experience for Polish agriculture.
We describe the diet of introduced European hedgehogs Erinaceus europaeus (Linnaeus, 1758) in a New Zealand dryland system and provide the first quantitative analysis of food selectivity for this species. We also describe and compare the diets of nine hedgehogs and measure dietary overlap between these individuals. The most commonly eaten foods were beetles, including rare native species (in 94% of droppings), earwigs (92%), spiders (25%) and native skinks (14%). Remains of at least three skinks were found in one dropping. Earwigs and darkling beetles (Tenebrionidae) were the most preferred food types, and Hymenoptera and cylindrical bark beetles (Colydiidae) were least preferred. Consumption of most foods mirrored their availability. Most individuals’ diets conformed to the pattern seen at the population scale, with 21–54% of dry faecal mass derived from beetles and 13–39% from earwigs. One animal frequently consumed large amounts of fruit. Dietary overlap between pairs of individuals was high (mean Horn’s index, 0.84). This may be the result of limited opportunities to diversify in a very moisture-limited and low diversity habitat.
This study assesses the extent of midwinter activity (June-July, 1996, 1998) in an island population of lesser short-tailed bat (Mystacina tuberculata) located at the southern limit (= highest latitude) of the species' distribution. Activity of radio-tagged bats (n = 22 bats) was monitored over 38 nights (years combined). A mean ± SE of 64.1 ± 6.5% (range = 0-100%) of radio-tagged bats flew on each night monitored when mean minimum temperature was 3.4 ± 0.5°C. Temperatures ranged from -1.0 to 8.9°C, and 33% of tagged bats flew on the coldest night. Video-monitoring revealed high levels of activity at 11 large communally occupied tree roosts on 100% of nights monitored (n = 31 nights, years combined). Mean minimum temperatures on these nights was 3.0°C ± 0.5 (range = -1.4-7.1). Periods of activity were associated with feeding, social displays and changing roost sites. Movements of bats were dynamic with large numbers emerging from and entering roosts, often simultaneously, throughout most of the night (x = 81.9 ± 3.3% of night). Maximum numbers of active bats in tree cavities at one time numbered > 100 individuals on 75% of nights monitored. These included nine nights when individuals numbered > 500, and five nights when individuals numbered >1,000 (maximum = 1,443). Radio-tagged bats spent 57.1 ± 9.7% of time monitored roosting alone and the remainder roosting communally. They changed roost site on average every 4.2 ± 0.8 days moving between a total of 35 different roosts. Roosts were often re-used either by the same individual or by several different bats. Most radio-tagged bats visited communal night roosts that were different from those they had used during the day, with up to eight radio-tagged individuals visiting simultaneously. Lower levels of activity were recorded at six roosts that were occupied on the same nights as large active communal roosts. Video-monitoring over a total of 31 nights revealed external activity at these roosts on only 11 nights (35.4%). One radio-tagged bat did not emerge for 13 days. 1 suggest that winter activity may not be as energetically expensive for M. tuberculata as for many other cold-temperate bat species. Their ability to forage on terrestrial invertebrates, which are not commonly available to other species, and to select different roost sites where they could either remain active or relatively inactive, may allow them to be active more frequently and for longer durations.
Weather and climatic conditions may impact on many aspects of bird populations, including population size, the timing of breeding and synchrony between these variables in local populations. We examined synchrony in population size and the laying date of two starling Sturnus vulgaris populations 25 km apart, at Ohau and Belmont, in New Zealand. Data were collected in nest-boxes in both study plots from 1970 to 2003. Additionally we investigated possible relationships with a large geographical climate index, the El Niño Southern Oscillation (ENSO). Starlings at Ohau bred significantly earlier than at Belmont. The difference in the median of year median date of laying the first egg was 3 days. Simultaneously, the percent of nest boxes used by birds was much higher in Ohau (86%, SE = 4.1) than in Belmont (52%, SE = 2.9). However, we did not find a significant relationship between median dates of laying and the percent of nest boxes used by birds in each breeding season in the two populations. Furthermore, we found no influence of ENSO on (potential) synchrony in starlings’ breeding parameters. We suggest that lack of synchrony between two close local populations, both in percentage of occupied nest boxes and time of laying, is due to starlings responding to very local conditions, like food availability. We urge future studies to take advantage of spatially close populations.
The microarchitecture of the cover hairs, wool hairs and tactile (sinus) hairs of feral, New Zealand White and Angora rabbits was studied by means of scanning electron microscopy. The morphology and variability of the cuticular scale patterns, hair cortex, medullary arrangement and profile of the hairs are described, illustrated and compared with findings resulting from conventional light microscopy, cuticular casting and medullary impregnation. All parameters examined in cover hairs presented a considerable variation along the length of the hair shaft. In wool hairs, in contrast, only the cuticular scale pattern was subject to manifest segmental variation, whereas the shaft diameter, cortical profile and medullar composition changed little over the entire length of the hair. The tactile hairs of the head were characterised by a round profile of the hair shaft, a cylindrical central medullar canal, and a thick cortex covered by cuticular scales that were arranged in a waved pattern and oriented transversally in relation to the longitudinal axis of the hair. It was concluded that the scanning electron microscopic observation of hair samples is a fast and valuable method for identifying hair types with useful applications in different disciplines such as mammalian biology, the textile industry and forensic medicine.
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