9,031 research outputs found
Marine mammal tourism in the Bay of Plenty, New Zealand : effects, implications and management : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Marine Ecology at Massey University, Albany, New Zealand
Worldwide expansion of marine mammal tourism over recent decades has raised international concerns in terms of the effects of these tourism practices on the species they target. Moreover, the growth and success of the industry have often outpaced conservation planning, including in New Zealand. To illustrate, tour vessels have been operating for ca. 25 years in the Bay of Plenty (BOP), situated on the east coast of North Island, New Zealand. By 2010, a total of eight permits had been granted across the region. However, development of this local industry occurred without any baseline data on species occurrence, distribution, habitat use or behaviour.
This study sought to assess the historical occurrence of the marine mammal species off the BOP and determine their spatial and temporal distribution. Current distribution, density and group dynamics were examined for common dolphins (Delphinus sp.) and New Zealand fur seals (Arctocephalus forsteri), the two most frequently encountered species in the BOP and therefore, the primarily targeted species by tour operators. The extent of anthropogenic interactions with common dolphins was investigated and their effects on dolphin behaviour examined. The number of common dolphin individuals closely interacting with tour vessels was estimated and dolphin-vessel interactions were quantified to assess repetitive encounters.
In the absence of previously undertaken systematic dedicated surveys, the present study investigated the historical spatial and temporal occurrence of dolphins, whales and pinnipeds in the BOP region. The examination of opportunistic data, collected between December 2000 and November 2010 via various platforms of opportunity including but not limited to tour vessels, identified fourteen species of dolphins, whales and pinnipeds occurring in the region. Confidence criteria in successful species identification were assigned based on observer expertise, diagnostic features of reported species and percentage of records reported by observer type. Common dolphins were the most frequently encountered species, followed by killer whales (Orcinus orca), bottlenose dolphins (Tursiops truncatus) and New Zealand fur seals, other species being infrequently encountered. A detailed examination of common dolphin habitat use
revealed discrepancies with previous findings (e.g. higher use of shallower waters), possibly explained by inherent biases to the opportunistic dataset.
Dedicated surveys, conducted between November 2010 and May 2013, investigated the current distribution, density and habitat use of common dolphins and New Zealand fur seals. Both species exhibited a strong seasonality with contrasting occurrence in summer and autumn for common dolphins and in winter and spring for fur seals. Dolphin seasonality is suggested to be linked to movements into deeper offshore waters and/or potentially to neighbouring regions (i.e. the Hauraki Gulf) and most likely related to foraging opportunities. Fur seal seasonality suggests that the western BOP supports a non-breeding colony and that foraging reasons may explain the species occurrence in the region. Higher density of common dolphins and fur seals identified over the shelf break and reefs can be explained by enhanced productivity.
First application of Markov chain analyses to common dolphin within oceanic waters, allowed examination of the effects of tourism activities on common dolphins in the BOP. Dolphin foraging behaviour was significantly affected, as dolphins spent less time foraging during interactions with tour vessels and took longer to return to foraging once disrupted by vessel presence. Disruption to feeding may be particularly detrimental to common dolphins in the BOP open oceanic habitat, where prey resources are typically widely dispersed and unpredictable. While the overall level of tour operator compliance with regulations in the bay was relatively high, non-compliance was recorded with regards to swimming with calves and extended time interacting with dolphins.
Evidence of repetitive interactions between tour vessels and common dolphins were examined using photo-identification to assess potential cumulative impacts. An estimated minimum of 1,278 common dolphin individuals were identified in the region, for which the majority (86.9%) showed low levels of site fidelity (i.e. only one encounter). At least 61.7% of identified dolphins were exposed to tour vessel interactions. However, spatial (i.e. between the western and eastern sub-regions) and temporal (i.e. daily, seasonal and annual) cumulative exposure to tourism activities was observed for less than 10% of these individuals. This is likely explained by tour operators âhanding overâ groups or returning to areas preferentially frequented by
dolphins (i.e. presumed foraging hotspots). Due to the opportunistic methods used for photo-identification, these results are indicative only of the absolute minimum of repeated interactions common dolphins may face in the region.
The present thesis represents the first comprehensive assessment of marine mammal tourism in the BOP. It offers important contributions to research and conservation in this area via the critical assessment of historical occurrence of marine mammals in the region. This thesis also provides comprehensive and detailed insights into common dolphin and New Zealand fur seal temporal and spatial distribution in the area. This can serve management agencies to implement efficient conservation plans. While identifying that tourism operations significantly affect common dolphin behaviour and repetitive interactions result in cumulative exposure, this thesis supports adaptive management and further long-term monitoring of marine mammal species in general, and in the BOP region more specifically
A New World Order: Explaining the Emergence of the Classical Gold Standard
The classical gold standard only gradually became an international monetary regime after 1870. This paper provides a cross-country analysis of why countries adopted when they did. I use duration analysis to show that network externalities operating through trade channels help explain the pattern of diffusion of the gold standard. Countries adopted the gold standard sooner when they had a large share of trade with other gold countries relative to GDP. The quality of the financial system also played a role. Support is found for the idea that a weak gold backing for paper currency emissions, possibly because of an unsustainable fiscal position or an un-sound banking system, delayed adoption. A large public debt burden also led to a later transition. Data are also consistent with the idea that nations adopted the gold standard earlier to lower the costs of borrowing on international capital markets. I find no evidence that the level of exchange rate volatility or agricultural interests mattered for the timing of adoption.
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Why Do Countries Peg the Way They Peg? The Determinants of Anchor Currency Choice
Conditional on choosing a pegged exchange rate regime, what determines the currency to which countries peg or âanchorâ their exchange rate? This paper aims to answer this question using a panel multinomial logit framework, covering more than 100 countries for the period 1980-1998. We find that trade network externalities are a key determinant of anchor currency choice, implying that there are multiple steady states for the distribution of anchor currencies in the international monetary system. Other factors found to be related to anchor currency choice include the symmetry of output co-movement, the currency denomination of debt, and legal or colonial origins
Isospin Splitting in the Pion-Nucleon Couplings from QCD Sum Rules
We use QCD sum rules for the three point function of a pseudoscalar and two
nucleonic currents in order to estimate the charge dependence of the pion
nucleon coupling constant coming from isospin violation in the strong
interaction. The effect can be attributed primarily to the difference of the
quark condensates and . Assuming that the pi0 is a pure
isostate we obtain for the splitting between the coupling of proton and neutron
to the neutral pion an interval of [0.008 ; 0.023], the uncertainties coming
mainly from the input parameters. In order to obtain the coupling to a physical
pi0 we have to take pi - eta mixing into account leading to an interval of
[0.012 ; 0.037]. The charged pion nucleon coupling is found to be the average
of the two neutral ones. Electromagnetic effects are not included.Comment: contributed talk at CIPANP97 (Big Sky, Montana); 3 pages
(aipproc.sty), no figure
Losing our Marbles in the New Century? The Great Rebalancing in Historical Perspective
Great attention is now being paid to global imbalances, the growing U.S. current account deficit financed by growing surpluses in the rest of the world. How can the issue be understood in a more historical perspective? We seek a meaningful comparison between the two eras of globalization: "then" (the period 1870 to 1913) and "now" (the period since the 1970s). We look at the two hegemons in each era: Britain then, and the United States now. And adducing historical data to match what we know from the contemporary record, we proceed in the tradition of New Comparative Economic History to see what lessons the past might have for the present. We consider two of the most controversial and pressing questions in the current debate. First, are current imbalances being sustained, at least in part, by return differentials? And if so, is this reassuring? Second, how will adjustment take place? Will it be a hard or soft landing? Pessimistically, we find no historical evidence that return differentials last forever, even for hegemons. Optimistically, we find that adjustments to imbalances in the past have generally been smooth, even under a regime as hard as the gold standard.
EVOLUTION OF A STRING NETWORK IN BACKGROUNDS WITH ROLLING HORIZONS
We discuss the temporal variation of the equation of state of a classical
string network, evolving in a background in which the Hubble radius 1/H shrinks
to a minimum and then re-expands to infinity. We also present a method to look
for self-consistent non-vacuum string backgrounds, correponding to the
simultaneous solution of the gravi-dilaton backgrounds equations and of the
string equations of motion.Comment: 19 pages, plain tex, no figures, to appear in "String gravity and
physics at the Planck energy scale" (World Scientific, Singapore, 1995
Foreign Capital and Economic Growth in the First Era of Globalization
We explore the association between income and international capital flows between 1880 and 1913. Capital inflows are associated with higher incomes per capita in the long-run, but capital flows also brought income volatility via financial crises. Crises also decreased growth rates of income per capita significantly below trend for at least two years leading to important short term output losses. Countries just barely made up for these losses over time, so that there is no conditional long-run income loss or gain for countries that experienced crises. This is in contrast to the recent wave of globalization when capital importing countries that experienced a crisis seemed to grow relatively faster over fixed periods of time. We discuss some possibilities that can explain this finding.
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