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Biodiversity loss is a major global challenge of the 21st century. Ultimately, extinctions of species are determined by birth and death rates; thus, conservation management of at-risk species is dependent on robust demographic data. In this study, data gathered from 381 (227 females, 154 males) long-finned pilot whales (Globicephala melas edwardii) that died in 14 stranding events on the New Zealand coast between 2006 and 2017 were used to construct the first age- and sex-specific life tables for the subspecies. Survivorship curves were fitted to these data using (1) a traditional maximum likelihood approach, and (2) Siler’s competing-risk model. Life table construction and subsequent survival curves revealed distinct differences in the age- and sex-specific survival rates, with females outliving males. Both sexes revealed slightly elevated rates of mortality among the youngest age-classes (

Knowledge of population biological parameters can contribute to assessing the resilience of a population in the face of increasing anthropogenic pressures. Southern Hemisphere long-finned pilot whales (Globicephala melas edwardii) are susceptible to high rates of live stranding-related mortality. However, the biological parameters of this population largely are unknown. In this study, age, growth, allometry, and sexual dimorphism are described using teeth and external body measurements obtained from 515 male, 776 female, and 229 individuals of unknown sex, stranded on the New Zealand coastline between 1948 and 2017. Maximum ages of 31 and 38 years were estimated for males (n = 163) and females (n = 239), respectively. Females ranged in length from 160 to 500 cm (modal size class 400–449 cm) and males from 165 to 622 cm (modal size class 500–549 cm). Length-at-birth for both sexes was estimated at 170 cm using a logistic regression model. Growth models for both sexes indicated a preliminary rapid growth phase followed by a second phase of slower growth. For males, a two-phase growth model also indicated a moderate growth spurt around the average age at attainment of sexual maturity (ca.12–13 years). Asymptotic lengths were estimated at 570 and 438 cm for males and females, respectively. We found strong evidence of sexual size dimorphism, with males significantly larger than females for 13 of 14 external measurements. We also found sexual dimorphism with respect to shape, with males having proportionally longer pectoral fins, wider tail flukes, and taller dorsal fins, than females. Estimates of length-at-birth, maximum ages, and sexual shape dimorphism for G. m. edwardii differed from those previously reported for the North Atlantic subspecies (G. m. melas), which may indicate subspecies or population-level differences in morphology, longevity, and sociality.

Conservation monitoring of highly mobile species in relatively inaccessible habitats presents a considerable challenge to wildlife biologists. Effective conservation strategies require knowledge of cetacean ecology that is often challenging and expensive to obtain. Despite their caveats, stranding data represent an underused resource to study the long-term dynamics of cetacean populations. Using long-finned pilot whale (LFPW; Globicephala melas edwardii) strandings on the New Zealand coast as a case study, we present a novel approach to demonstrate how stranding data can inform conservation management of data-poor species. A total of 8571 LFPWs stranded on the New Zealand coast within a 40-year period between January 1978 and December 2017. Overall, where sex was recorded, mass stranded adults were significantly biased towards females, while a significant male bias was observed in juveniles. Strandings occurred in all months, though significant seasonal variation was evident, with 66% of stranding events reported during austral spring and summer months (October–February). Hot spot analysis (ArcGIS) identified the majority of LFPWs stranded at Golden Bay, Great Barrier Island, Stewart Island and the Chatham Islands, with emerging hot spot analysis (ArcGIS) used to identify spatiotemporal trends. While emerging hot spot analysis revealed no significant temporal trend in the annual frequency of stranding events or numbers of individuals stranded, it did reveal a significant spatiotemporal trend, with the numbers of stranded individuals declining in areas of the Far North, Coromandel, Canterbury, Otago and the Chatham Islands, and increasing in Golden Bay and Stewart Island. When combined with other contextual information, such trends help identify the most significant clusters of LFPW strandings on the New Zealand coast, provide baseline ecological data on a poorly understood subspecies, and can be used to guide conservation management of G. m. edwardii in New Zealand waters.

Male reproductive biology is described for the Southern Hemisphere long-finned pilot whale (Globicephala melas edwardii), a subspecies that regularly mass strands along the New Zealand coastline. Ten mass stranding events sampled over a 7-year period enabled assessments of key life history parameters. Sexual maturation in immature, maturing, and mature males was assessed using morphological data and histological examination of testicular tissue. Variation was observed in the age (11–15 years) and length (450–490 cm) at which individuals attained sexual maturity. Using Bayesian cumulative logit regression models, we estimated the average age and length at the attainment of sexual maturity to be 13.5 years and 472 cm, respectively. Combined testes weight, combined testes length, an index of testicular development (combined testes weight/combined testes length), and mean seminiferous tubule diameter were all good indicators of sexual maturity status. Combined testes length was the best nonhistological indicator, and all testicular measures were found to be better indicators of sexual maturation for G. m. edwardii than age or total body length. Sexual maturity was attained before physical maturity (> 40 years and 570 cm), and at a younger age and smaller body length than previously reported for Globicephala melas melas in the North Atlantic. Given the ease of collection, minimal processing, and applicability to suboptimal material collected from stranding events, future studies should assess the value of testicular size as an indicator of sexual maturity in pilot whales and other cetacean species. Estimates of the average age and length at sexual maturity for G. m. edwardii provided in this study may be used to inform population models required for conservation management of the subspecies, which is subject to high levels of stranding-related mortality.

The coastal distribution of Hector’s dolphins and their attraction to vessels make them easily accessible to commercial tour operations. For over 25 yr, tour operators have been undertaking view and swim-with-dolphin trips in Akaroa Harbour, New Zealand. Since 2003, auditory stimulants, in particular stones, have been provided during such swim encounters. The potential effects associated with such stimulants have not, until now, been examined. Here, we investigate the effects of stones and other human-induced noise on Hector’s dolphin behavior. The use of stones significantly affected how dolphins interacted with swimmers. Specifically, swimmers who used stones had a greater probability of close approaches by dolphins than those who sang or simply floated on the surface of the water. The number of close and sustained approaches was also significantly higher for swimmers using stones. Dolphins were more interactive with active swimmers, approaching closer and engaging for longer than with nonactive swimmers. Dolphins socializing had a tendency to be engaged longer with swimmers. The use of stones as an auditory

Here we present the first data describing the behavior of common dolphins (Delphinus sp.) in the Hauraki Gulf, New Zealand. Activity budgets are used to assess the effects of diel, season, depth, sea surface temperature, group size, and composition on dolphin behavior. Additionally, the presence/absence of Bryde's whale (Balaenoptera brydei) and Australasian gannet (Morus serrator) is examined in relation to dolphin behavior. Behavioral data were collected from 686 independent dolphin groups during boat-based surveys conducted between February 2002 and January 2005. Foraging (46.7%) and social (7.2%) were the most and least frequently observed behaviors, respectively. Travel (28.9%), mill (9.5%), and rest (7.7%) accounted for the remainder of the activity budget. Behavior varied seasonally, with the highest proportion of foraging and resting groups observed during the spring and autumn, respectively. Behavior also varied with water depth, with foraging animals observed in the deepest and resting groups recorded in the shallowest regions of the Hauraki Gulf. A correlation between group size and behavior was evident, although behavior did not vary with the composition of dolphin groups. Resting, milling, and socializing animals were more frequently observed in smaller group sizes. Foraging behavior was prevalent in both small and large group sizes, suggesting foraging plasticity exists within this population. Behavior differed between single- and multispecies groups, with foraging more frequent in multispecies groups. Resting, milling, or socializing was rarely observed in the presence of any associated species, indicating the primary mechanism for association is likely prey related.

Common dolphins Delphinus sp. are frequently targeted by tourism operations in New Zealand waters, yet there is a paucity of data on potential impacts faced by this species. Transition matrix models, used widely in population ecology, have recently been applied to behavioural transitions in order to provide successful management guidelines. We detail the use of Markov chain models to assess the impact of tourism activities on the behavioural state of common dolphins in the Hauraki Gulf, New Zealand. First-order time discrete Markov chain models were used to describe transition probabilities in both control and impact scenarios. The effect of boat interactions was quantified by comparing transition probabilities of both control and impact chains. Foraging and rest- ing bouts were significantly disrupted by boat interactions to a level that raises concern about the sustainability of this impact. Both the duration of bouts and the overall time spent in these 2 be- havioural states decreased. Foraging dolphins took significantly longer to return to their initial behavioural state in the presence of the tour boat. There was also an increased preference to shift behaviour to socialising or milling after tour boat interactions. Impacts identified in the present study are similar to those previously reported for bottlenose dolphins, a coastal species typically considered to be more susceptible to cumulative anthropogenic impacts.

Common dolphins, Delphinus sp., are one of the marine mammal species tourism operations in New Zealand focus on. While effects of cetacean-watching activities have previously been examined in coastal regions in New Zealand, this study is the first to investigate effects of commercial tourism and recreational vessels on common dolphins in an open oceanic habitat. Observations from both an independent research vessel and aboard commercial tour vessels operating off the central and east coast Bay of Plenty, North Island, New Zealand were used to assess dolphin behaviour and record the level of compliance by permitted commercial tour operators and private recreational vessels with New Zealand regulations. Dolphin behaviour was assessed using two different approaches to Markov chain analysis in order to examine variation of responses of dolphins to vessels. Results showed that, regardless of the variance in Markov methods, dolphin foraging behaviour was significantly altered by boat interactions. Dolphins spent less time foraging during interactions and took significantly longer to return to foraging once disrupted by vessel presence. This research raises concerns about the potential disruption to feeding, a biologically critical behaviour. This may be particularly important in an open oceanic habitat, where prey resources are typically widely dispersed and unpredictable in abundance. Furthermore, because tourism in this region focuses on common dolphins transiting between adjacent coastal locations, the potential for cumulative effects could exacerbate the local effects demonstrated in this study. While the overall level of compliance by commercial operators was relatively high, non-compliance to the regulations was observed with time restriction, number or speed of vessels interacting with dolphins not being respected. Additionally, prohibited swimming with calves did occur. The effects shown in this study should be carefully considered within conservation management plans, in order to reduce the risk of detrimental effects on common dolphins within the region.

Photo‐identification has been established as a helpful tool in cetacean research. However, no study to date has attempted to apply this method to short‐beaked common dolphins (Delphinus delphis L.). We present here the results of two studies that were conducted concurrently in Mercury Bay and the Hauraki Gulf on the north‐east coast of New Zealand's North Island. Methods for distinguishing between individual dolphins are discussed. Sighting records of recognisable individuals indicate that some common dolphins move between Mercury Bay and the Hauraki Gulf (100 km distance), as well as between Mercury Bay and Whakatane (200 km distance). Common dolphin abundance and site fidelity appeared to be greater in the Hauraki Gulf than in Mercury Bay. A selection of photographs of distinct individuals is presented to allow future studies to compare their sighting records to ours, which may help establish the extent of home ranges, site fidelity, and possibly even longevity for common dolphins.

The Vava'u island group in the northern part of the Kingdom of Tonga in the South Pacific has a growing reputation as a whale-watching destination. The pro-whaling organisation, the World Council of Whalers, with some local people, has, however, been actively promoting a resumption of whaling in Tonga. This study assesses the attitudes and characteristics of 'whale tourists' to the islands. Seventy-eight per cent of all tourists arriving by air, and around half those arriving by yacht, went whale watching. Both types of visitor opposed whale hunting; both types said they would be less likely to visit the islands if whales were hunted there. Consequently, any resumption of whaling or change in the protected status of whales would be likely to displace a large proportion of current visitors to Vava'u, resulting in a serious 'opportunity cost'. It seems unlikely that a whale-watching industry could coexist with a lethal use of whales in Tonga.

To date research on whale-watching has tended to focus on impacts on the whales. Management approaches often rely on minimum approach distances. An associated assumption is that whale-watchers wish to get close to whales. Studies of motivation for other recreational activities show that humans seldom undertake recreational activities for simplistic reasons. Thus, this study was developed to determine the influences over whale-watchers’ enjoyment, more specifically, to assess the importance of the geographical proximity of whales. Twelve whale-watch cruises at Tangalooma, Australia were surveyed and 704 questionnaires analysed. Results showed the number of whales and their behaviour, numbers of fellow passengers, cruise duration, boat construction and sea-sickness influenced satisfaction. The geographical proximity of the whales was not a major influence. Many whale-watchers (35 per cent) returned satisfied even when no whales were sighted. Whale-watching is not simply about getting close to whales, many other variables are important. A better understanding of the watchers, as well as the whales, will assist in the sustainable management of this growing tourism industry.

A study which tested the effectiveness of an education programme for managing tourists was conducted at Tangalooma, Australia. At this holiday resort tourists are able to hand-feed a group of wild dolphins which visit the shallow waters adjacent to the resort's beach. The education programme, which uses techniques derived from cognitive psychology and learning theory, attempted to prompt increased enjoyment, knowledge and improved environmental attitudes, intentions and behaviour in participants. The study, which compared a control group who were not exposed to the education with an experiment group who were, found that desirable changes did occur as a result of the programme. This research provides much needed evidence that education can be an effective means of managing tourists' interaction with wildlife and the natural environment © 1997 John Wiley & Sons, Ltd.

An industry based upon taking tourists to watch, swim and otherwise interact with dolphins and whales in the wild has expanded rapidly over the past decade. It is now a large and geographically dispersed activity which occurs in over 65 countries worldwide. One aspect of this industry involves interacting with dolphins and this has become particularly popular in Australia and New Zealand. There are many historical accounts of human-wild dolphin interaction and a detailed review of these records shows that the ‘new’ dolphin based tourism industry has developed from a long history of human-dolphin relationships. This comprehensive literature review also reveals that there are considerable risks, both for the dolphins and for the tourists as a result of these encounters. Risks include harassment, stress, injury and death for dolphins and also injury for humans. It is important that dolphin tourism operators, management agencies and tourists themselves are aware of these risks and manage their activities accordingly.

A program where wild bottlenose dolphins (Tursiops truncatus) are fed by tourists in shallow water adjacent to a wharf has been established at Tangalooma, Queensland, Australia. Up to nine dolphins attend the nightly feedings, and between 60 and 80 resort guests are permitted to hand feed these dolphins each night. Since this program began in 1992, the dolphins have increased in confidence and have started, at times, to make forceful contact with guests who enter the water to feed them. This paper categorizes such behavior as “pushy” and reports on a study which quantifies the “pushiness” of the dolphins which feed at Tangalooma. The study examines ecological variables which may determine how pushy the dolphins are at different feeding sessions. The number of dolphins attending a particular feeding significantly increases the pushiness. In addition, the presence of adult males at a feeding is likely to increase pushing. Tidal state also influences how pushy the dolphins are. At low tide, when the dolphins’mobility is restricted by the water depth, they are less likely to be pushy. Given the problems experienced in a number of other situations where wild animals are fed by humans, it is important to monitor carefully the escalation of pushy behavior in this dolphin feeding program, as it may be a precursor to more aggressive actions on the part of the dolphins.

Tourist interest in experiencing marine wildlife in their natural environment is growing. In particular, opportunities for interaction with marine mammals such as dolphins are becoming increasingly popular. Such interaction between humans and solitary dolphins has occurred throughout history; however, the dolphins at Monkey Mia in Western Australia are the only recorded group of dolphins which regularly interact with tourists. A previously unreported case of tourist-dolphin interaction is being developed at Tangalooma in Queensland, Australia. The development of this program is outlined in this paper and the current management of this interaction is considered.