Suchergebnisse

Context
Avian–human conflict is a growing issue in urban areas, yet studies of conflict tend to be species and situation specific and focus on landscape characteristics that generate or exacerbate the problem.

Aims
To determine characteristics of bird species that cause conflict in urban areas within their native range and to develop a model that can be used to assess the relative likelihood of a New Zealand species causing conflict in the future.

Methods
Ecological, behavioural and life-history characteristics of 33 conflict-causing species identified from the literature and 106 randomly selected non-conflict congeners were compared using an information-theoretic approach to multi-model selection and inference. Variables from the confidence set of models were used to develop a model that was applied to the New Zealand urban avifauna to provide a relative measure of a species' potential to generate conflict.

Key results
A model including only dietary breadth best explained the conflict (ωi = 0.833). Using dietary breadth, flocking, clutch size, granivory, territoriality and non-ground nesting – the confidence model set – New Zealand's native pukeko (Porphyrio porphyria), red-billed gull, (Larus scopulinus), and kākā (Nestor meridionalis) were identified as the three species most likely to generate conflict with urban residents.

Conclusions
Broad dietary requirements may allow a species to take advantage of novel and varied food sources in the urban environment and lead to population growth. Large populations at high density may amplify problems, exceeding residents' tolerance levels and resulting in conflict. Species characteristics relating to nesting, sociality and body size were found to be uninformative.

Implications
Species with a broad diet, particularly those identified by this study as having a high potential for conflict, should be the focus of monitoring to identify population growth and the emergence of problems in urban areas. This will allow proactive implementation of management, improving the likelihood of conflict mitigation.

Pro-environmental behaviors (PEBs) may be associated with a personal relationship with nature. We conducted a quasi-experiment with 423 residents who had or had not actively participated in a tree-planting scheme and lived in 20 neighborhoods that differ in their greenness level. We tested whether exposure to nature (specified by the amount of vegetation cover in residents' neighborhoods) and/or past PEB (specified by tree-planting participation) was associated with residents' PEB and whether key psychological constructs would mediate these relationships. Structural equation mediation models revealed that the level of neighborhood vegetation and involvement in the planting scheme explained 46% of the variance in PEB, with connection to nature, the use of nature for psychological restoration, and environmental attitudes mediating the relationships. Connection to nature was more strongly associated with engagement in PEB than the use of nature for psychological restoration and environmental attitudes.

Although feral horses are a common management problem in numerous countries, detailed and long-term demographic studies are rare. We measured the age and sex structure, and pregnancy, birth and death rates in a population of 413 feral horses in New Zealand during 1994–98 and used them to construct a model simulating population growth. Survivorship increased with age (0–1 years old = 86.8%, 1–2 = 92.3%, 2–4 = 92.4%, ≥�4 years old = females 94%, males 97% per annum). Birth sex ratio parity, a slight female bias in the adult sex ratio (92 males per 100 females) and higher adult male survivorship indicated lower average survivorship for young males than females that was not detectable in mortality statistics. Pregnancy and foaling rates for mares ≥�2 years old averaged 79 and 49%, respectively. Foaling rates increased as mares matured (2–3-year-old mares = 1.9%, 3–4 = 20.0%, 4–5 = 42.1%, ≥�5 = 61.5% per annum). Young mares had higher rates of foetal and neonatal mortality (95% of pregnancies failed and/or were lost as neonatal foals in 2–3-year-old mares, 70.6% in 3–4, 43.2% in 4–5, and 31% in mares ≥�5 years old). Population growth was 9.6% per annum (9.5–9.8, 95% CI) without human-induced mortalities (i.e. r = 0.092). Our model, standardised aerial counts, and historical estimates of annual reproduction suggest that the historical sequence of counts since 1979 has overestimated growth by ~50% probably because of improvements in count effort and technique.