title: Water relations of the endemic New Zealand frogs Leiopelma archeyi, L. Hamiltoni and L. Hochstetteri

authors: Cree, Alison

abstract: Aspects of habitat and water balance physiology were compared between the endemic and anatomically primitive New Zealand frogs Leiopelma archeyi, L. hamiltoni and L.  hochstetteri. Field studies in an area of the Coromandel Range showed that the partially sympatric L. archeyi and L. hochstetteri had nearly disjunct distributions. L. archeyi occurred in terrestrial habitats on the forested ridgetops, whereas most L. hochstetteri were found in semiaquatic habitats along the edges of streams. L. archeyi also showed less preference for water than L. hochstetteri in the laboratory. Climatic conditions in the ridgetop habitat of L. archeyi were usually cool and humid, and resembled those previously reported for the allopatric and completely terrestrial L. hamiltoni.
In laboratory studies, all three species dehydrated rapidly in dry conditions. Resistance to evaporative water loss (EWL) was similar to that for a free water surface. L. archeyi and L. hamiltoni rehydrated rapidly (in 1-2 h) when returned to shallow water after dehydration to 9-15% weight loss. Rapid rehydration was due to increased water uptake through ventral skin and to reduced bladder urine accumulation (cutaneous and antidiuretic water balance responses). L. hochstetteri rehydrated very slowly (rehydration incomplete within 16 h) and showed only an antidiuretic response. L. hochstetteri also rehydrated more slowly from moist soil when compared with L. archeyi.
Treatment with arginine vasotocin (AVT, 7 x 10⁻¹¹ mol g⁻¹) produced water balance responses similar to those seen during rehydration. L. archeyi and L. hamiltoni placed in shallow water showed rapid water retention, reaching weight gains of 31% and 29% respectively 4-5 h after treatment. L. hochstetteri gained weight at a slow and linear rate (9% over 9 h). Unlike L. archeyi and L. hamiltoni, L. hochstetteri showed no increase in cutaneous water uptake, and water retention was attributed solely to antidiuresis.
In vitro experiments confirmed that AVT (3 x 10⁻⁸ mol 1⁻¹) caused increased osmotic water flow (OWF) through ventral pelvic skin of L. archeyi and L. hamiltoni. However, pelvic skin from L. hochstetteri and ventral pectoral and dorsal skin from all three species showed no hydroosmotic response. The bladders of the three species showed small increases in OWF in response to AVT. In vivo, glomerular filtration rate fell following AVT treatment in all species, although the effect on L. hochstetteri was not statistically significant.
Pelvic skin of L. archeyi showed no obvious structural specialisation for rapid water uptake, when examined using light and scanning electron microscopy. Pelvic skin was smooth, structurally similar to non-glandular areas of pectoral or dorsal skin, and less vascularised than pelvic skin of L. hochstetteri.
Adults of all three species were ureotelic. In the terrestrial eggs and larvae of L. archeyi, intracapsular larvae were ammonotelic, but most larvae became ureotelic within 4 d after hatching. The eggs had no resistance to EWL, but absorbed water rapidly from moist surfaces. Male parental care (egg brooding, larval transport) led to reduced EWL from eggs and hatched larvae of L. archeyi. 
This study demonstrates that the presence of a cutaneous hydroosmotic response varies between adults of the three species in an inverse manner with habitat water availability. It also supports previous studies indicating a closer ecological similarity and evolutionary relationship between L. archeyi and L. hamiltoni, than between either and L. hochstetteri.

text: Water relations of the endemic New Zealand frogs Leiopelma archeyi, L. Hamiltoni and L. Hochstetteri Aspects of habitat and water balance physiology were compared between the endemic and anatomically primitive New Zealand frogs Leiopelma archeyi, L. hamiltoni and L.  hochstetteri. Field studies in an area of the Coromandel Range showed that the partially sympatric L. archeyi and L. hochstetteri had nearly disjunct distributions. L. archeyi occurred in terrestrial habitats on the forested ridgetops, whereas most L. hochstetteri were found in semiaquatic habitats along the edges of streams. L. archeyi also showed less preference for water than L. hochstetteri in the laboratory. Climatic conditions in the ridgetop habitat of L. archeyi were usually cool and humid, and resembled those previously reported for the allopatric and completely terrestrial L. hamiltoni.
In laboratory studies, all three species dehydrated rapidly in dry conditions. Resistance to evaporative water loss (EWL) was similar to that for a free water surface. L. archeyi and L. hamiltoni rehydrated rapidly (in 1-2 h) when returned to shallow water after dehydration to 9-15% weight loss. Rapid rehydration was due to increased water uptake through ventral skin and to reduced bladder urine accumulation (cutaneous and antidiuretic water balance responses). L. hochstetteri rehydrated very slowly (rehydration incomplete within 16 h) and showed only an antidiuretic response. L. hochstetteri also rehydrated more slowly from moist soil when compared with L. archeyi.
Treatment with arginine vasotocin (AVT, 7 x 10⁻¹¹ mol g⁻¹) produced water balance responses similar to those seen during rehydration. L. archeyi and L. hamiltoni placed in shallow water showed rapid water retention, reaching weight gains of 31% and 29% respectively 4-5 h after treatment. L. hochstetteri gained weight at a slow and linear rate (9% over 9 h). Unlike L. archeyi and L. hamiltoni, L. hochstetteri showed no increase in cutaneous water uptake, and water retention was attributed solely to antidiuresis.
In vitro experiments confirmed that AVT (3 x 10⁻⁸ mol 1⁻¹) caused increased osmotic water flow (OWF) through ventral pelvic skin of L. archeyi and L. hamiltoni. However, pelvic skin from L. hochstetteri and ventral pectoral and dorsal skin from all three species showed no hydroosmotic response. The bladders of the three species showed small increases in OWF in response to AVT. In vivo, glomerular filtration rate fell following AVT treatment in all species, although the effect on L. hochstetteri was not statistically significant.
Pelvic skin of L. archeyi showed no obvious structural specialisation for rapid water uptake, when examined using light and scanning electron microscopy. Pelvic skin was smooth, structurally similar to non-glandular areas of pectoral or dorsal skin, and less vascularised than pelvic skin of L. hochstetteri.
Adults of all three species were ureotelic. In the terrestrial eggs and larvae of L. archeyi, intracapsular larvae were ammonotelic, but most larvae became ureotelic within 4 d after hatching. The eggs had no resistance to EWL, but absorbed water rapidly from moist surfaces. Male parental care (egg brooding, larval transport) led to reduced EWL from eggs and hatched larvae of L. archeyi. 
This study demonstrates that the presence of a cutaneous hydroosmotic response varies between adults of the three species in an inverse manner with habitat water availability. It also supports previous studies indicating a closer ecological similarity and evolutionary relationship between L. archeyi and L. hamiltoni, than between either and L. hochstetteri.

year: 1986

title: The Problem of Counterfeit Refrigerants

authors: Carson, James K.

abstract: This paper discussed the problem of conterfeit refrigerants

text: The Problem of Counterfeit Refrigerants This paper discussed the problem of conterfeit refrigerants

year: 2015

title: Defence not defiance: The shaping of New Zealand’s volunteer force

authors: Clayton, Garry James

subjects: New Zealand Army history

abstract: In the latter half of the nineteenth century and the first decade of the twentieth New Zealand's land defences were primarily the responsibility of its Volunteer Force. This Force over a period of fifty-two years evolved from ill-considered vigilante bands to a well organised and disciplined Army. This thesis examines the evolution of this Volunteer Army in chronological sequence concentrating on the factors which shaped and developed it.
The preface provides a brief outline of this study on New Zealand's Volunteer Force. The thesis then presents the history of the Force in eight chapters. These chapters are in four basic divisions. The first section, of three chapters. examines the origins of the Force, its role in the New Zealand Wars and its subsequent development in the period of tenuous peace during the 1870's . The second section, comprising of two chapters only, examines the transformation of the Volunteers from a military body which primarily looked inward. into a Force which concentrated on protecting the nation's main ports. The third section , also comprising two chapters , then views the development of this coastal protection Force into a Colonial Army, able and willing to provide for the nation's own security as well as expeditionary units to· serve with the British Imperial Forces ·. The last Section, of one Chapter only, concentrates on the demise of Volunteering and the moves to compulsory military training. The conclusion then draws together the analytical threads of the thesis. 
As the thesis is extensive in its coverage of time, it is only possible to outline the very nature of Volunteering. It will be for Regimental Historians to show the uniqueness of each of the 658 different units that comprised the New Zealand Volunteer Force over its fifty-two years of existence. What this broad survey does do, however, is provide a unique window for the examination of the development of an embryonic Colonial Army in the context of a developing nation.

text: Defence not defiance: The shaping of New Zealand’s volunteer force In the latter half of the nineteenth century and the first decade of the twentieth New Zealand's land defences were primarily the responsibility of its Volunteer Force. This Force over a period of fifty-two years evolved from ill-considered vigilante bands to a well organised and disciplined Army. This thesis examines the evolution of this Volunteer Army in chronological sequence concentrating on the factors which shaped and developed it.
The preface provides a brief outline of this study on New Zealand's Volunteer Force. The thesis then presents the history of the Force in eight chapters. These chapters are in four basic divisions. The first section, of three chapters. examines the origins of the Force, its role in the New Zealand Wars and its subsequent development in the period of tenuous peace during the 1870's . The second section, comprising of two chapters only, examines the transformation of the Volunteers from a military body which primarily looked inward. into a Force which concentrated on protecting the nation's main ports. The third section , also comprising two chapters , then views the development of this coastal protection Force into a Colonial Army, able and willing to provide for the nation's own security as well as expeditionary units to· serve with the British Imperial Forces ·. The last Section, of one Chapter only, concentrates on the demise of Volunteering and the moves to compulsory military training. The conclusion then draws together the analytical threads of the thesis. 
As the thesis is extensive in its coverage of time, it is only possible to outline the very nature of Volunteering. It will be for Regimental Historians to show the uniqueness of each of the 658 different units that comprised the New Zealand Volunteer Force over its fifty-two years of existence. What this broad survey does do, however, is provide a unique window for the examination of the development of an embryonic Colonial Army in the context of a developing nation.

year: 1990