A reserve for feral sheep on Pitt Island,Chatham group,New Zealand

Abstract

A scientific reserve of 200 ha has been created on Pitt Island, Chatham Islands for some 300 sheep from a flock of merino origin which has been feral for about 70 years. The reserve has a history of burning-off, and of grazing by cattle, sheep, and pigs. Transects have been established to follow changes in the vegetation. Although the original sheep were white, about 90% of the feral sheep have pigmented fleeces. Self-shedding of the wool is common in the population. The contribution that feral mammals can make to genetic conservation, and the problems that they pose to other conservation priorities, are discussed.     

Feral cats on Stewart Island; their foods,and their effects on kakapo

Abstract

The foods of feral house cats (Felis catus) on Stewart Island were determined by examining 229 scats collected during surveys of the distribution and numbers of kakapo (Strigops habroptilus), an endangered ground-parrot species. Rats occurred in 93% of the scats, birds in 44. 1%, wetas (large orthopterans) in 26.2%, and lizards in 24.0%. Twelve (70.6%) of the 17 species of birds were native. Kakapo remains were found in 6 (5.1%) of the 118 scats collected from areas where kakapo have been recorded.     

New records of rotifers from the South Island lakes,New Zealand

Thirty-five lakes in the South Island of New Zealand were surveyed for rotifers during 1988–1991. Of 85 taxa identified, 31 are first records for New Zealand, bringing the rotifers recorded from the country to 331. Four species (Keratella australis, K. slacki, Lecane herzigi and L. tasmaniensis), previously recorded as endemic forms only in Australia, are now added to the New Zealand checklist. Several of the new records are photographed, and scanning electron micrographs of the trophi are shown. Comments are made on the Australasian endemics and rotifer biogeography in New Zealand.     

Toxic and noxious phytoplankton in Big Glory Bay,Stewart Island,New Zealand

Diurnal vertical profile sampling of the water column, during a fish killing bloom of the raphidophycean alga Heterosigma akashiwo, revealed a phytoplankton population otherwise composed almost entirely of a variety of dinoflagellates. Of these Glenodinium danicum, Dinophysis acuta, Polykrikos schwartzii, Ceratium furca and Gyrodinium spirale were predominant. The distribution of the major species within the phytoplankton were documented and evidence of synchronous vertical migration of H. akashiwo, G. danicum and P. schwartzii was observed. Extracts of shellfish obtained during the bloom and tested by mouse bioassay showed no PSP toxicity but a marginal degree of DSP toxicity. During a subsequent one year phytoplankton monitoring programme another potentially noxious species (Chaetoceros convolutus) appeared and the seasonal reoccurrence of species present during the bloom (e.g. H. akashiwo) was observed. Important year to year differences in the summer phytoplankton (diatom versus flagellate dominated populations) were apparent and analysis of climate data showed that these differences related to different weather conditions prevailing during the two summer periods sampled. The data suggest the fish killing bloom was giving a chance to develop by a prolonged period of warm, calm weather (during which several heavy rainfall events occurred) leading to stable hydrographic conditions (i.e. stratification) and an increase in the retention time of water within the bay.     

Eel protection measures within the Manapouri hydro-electric power scheme,South Island,New Zealand

Variation in developmental rate from fertilization to swim-up, and body size at swim-up, may affect the growth and survival of young-of-the-year fish. Fish egg size (diameter) is often positively correlated to adult female size, but whether increased egg size equates to higher egg nutrient content and subsequently improved embryo/larval performance, remains unclear. Artificially fertilized northern pike eggs from individual females (total length 400–800 mm) were cultured under temperature controlled laboratory conditions to test the hypothesis that female body size positively influences egg size and the amount of specific nutrients (carbon, nitrogen, phosphorus, and fatty acids) allocated to eggs. We further hypothesized that greater egg nutrient content would positively influence egg survival, developmental rate, and the size of swim-up fry. These hypotheses were investigated in the context of two different northern pike spawning strategies (early season tributary vs. late season deep shoal spawning). Nutrients were allocated conservatively in northern pike eggs, showing very little variation in nutrient concentrations, but the total mass of all egg nutrients increased linearly with egg dry mass. Neither egg dry mass nor nutrient content (concentration or mass), were related to either egg diameter or female body size. The mass of individual egg nutrients was, however, strongly correlated with egg dry mass (r ² range 0.62 to 0.99 for individual nutrients) and positively related to the total length of swim-up fry (r ² = 0.58). The eggs of late spawning pike had significantly greater dry mass (average = 3.02 mg/egg) and developed more rapidly to swim-up (average = 17.89 days) than did those of early spawners (average = 2.28 mg/egg, 19.05 days). Our results indicate that egg quality may be best assessed by egg dry mass, which was correlated with greater nutrient mass and increased swim-up fry body length, as opposed to egg diameter or female body size which showed no correlation to egg nutrient composition and egg/larval performance. Guest editors: J. M. Farrell, C. Skov, M. Mingelbier, T. Margenau & J. E. Cooper International Pike Symposium: Merging Knowledge of Ecology, Biology, and Management for a Circumpolar Species     

Genetic variation,population structure and cryptic species within the black mudfish,Neochanna diversus,an endemic galaxiid from New Zealand

To investigate the phylogenetic relationships and geographical structure among landlocked populations of the black mudfish, Neochanna diversus, mitochondrial DNA nucleotide sequence data were sampled from seven populations from the Waikato and Northland regions of New Zealand. The complete D-loop region was sequenced from 70 individuals, with 913 bp from the tRNA-pro end used in population and phylogenetic analysis. A tandem repeat array, which ranged in size up to 200 bp, was found in most populations at the 3′ end of the D-loop that was not able to be aligned for analysis. Of the seven sites sampled, two from Northland exhibited significant sequence divergence from all other sites. There was also a clear distinction among remaining Northland sites and those from the Waikato. An additional 518 bp segment of the 16S region was sequenced from all sites and compared with the other New Zealand mudfish species, N. apoda, N. burrowsius and the Tasmanian mudfish Galaxias (Neochanna) cleaveri using Galaxias maculatus as an outgroup. Both D-loop and 16S sequence data provided strong evidence for a cryptic species of mudfish present in Northland. The significant genetic structure apparent in the black mudfish appears most probably to be attributed to geological conditions during the Pliocene, where peat wetlands became apparent in the Waikato while Northland consisted of disjunct ‘islands’. Conservation and management of these populations must take into account the historical processes that have shaped these patterns of genetic diversity.     

Prospects for the eradication of rats from a large inhabited island: community based ecosystem studies on Great Barrier Island, New Zealand

Great Barrier Island (c. 27,400 ha) is the largest off-shore Island in New Zealand. Some of the most serious introduced mammalian pests of New Zealand are absent, but feral cats and rodents are present. Community based trusts are spear-heading ecological studies to support conservation and a pest eradication programme. Rodent numbers are greatest in late summer/autumn and lowest in winter/early spring. Maximum abundances were recorded in riparian and coastal vegetation, and in mature forest. Monitoring shows that trapping alone is not able to reduce rat numbers sufficiently for safety in avian re-introductions. A combination of trapping and strategically pulsed toxin baits, however, achieved low levels of rats. Ecosystem recovery is demonstrated by increases in key tree seedlings, large invertebrates and lizards in managed compared to unmanaged areas, and by the survivorship of translocated robins (Petroica longipes). The Great Barrier Island Charitable Trust is communicating these benefits, and associated risks, to the Island community, with a view to promoting pest eradication as a key component in an ecology-based economy, centred on eco-tourism.

Isozyme analysis of Galaxias species (Teleostei: Galaxiidae) from the Taieri River, South Island, New Zealand: a species complex revealed

We examined genetic differentiation among 23 samples of non-migratory river galaxias from 17 streams in the Taieri River system, South Island, New Zealand. Four major genetic types were found, two of which occur in narrow sympatry in one location. These were compared with topotypical material representing Galaxias anomalus from the Clutha system (Otago) and G. vulgaris from the Waimakariri system (Canterbury) in order to establish identity. Morphological examination of these four major genetic types revealed consistent concomitant differences. The results suggest that there are at least three species of river galaxias in the Taieri system: G. anomalus, G. vulgaris and at least one previously undescribed species. We propose that the genetic structuring and subsequent speciation of this group has been promoted by the absence of the marine juvenile phase that is found in five other members of the genus native to New Zealand. This structuring may be exacerbated by population fragmentation over the last century owing to the negative influence of introduced trout. The phylogenetic diversity within the river system mirrors the diverse flora and invertebrate fauna of the region, and has conservation implications that parallel those resulting from our improved knowledge of the New Zealand herpetofauna through the application of genetic analysis.     

Understanding Attitudes Toward the Control of Nonnative Wild and Feral Mammals: Similarities and Differences in the Opinions of the General Public,Animal Protectionists,and Conservationists in New Zealand (Aotearoa)

Lethal control is used extensively in New Zealand to control nonnative nonhuman mammals. Respondents were surveyed about 8 mammal groups considered pests and their attitudes toward their control and pest status. They also identified the most appropriate method of control for the 8 different mammals. Information was gathered from 3 groups of respondents: nonhuman animal protectionists, conservationists, and the general public. Conservationists routinely rated all animal groups as more severe pests than the general public or animal protectionists, who provided the lowest scores. Rats, stoats, brushtail possums, and rabbits were identified as the 4 most serious pests by all 3 groups. Conservationists were 5.7 and 2.6 times more likely to prefer a lethal method of control than protectionists and the general public, respectively. For all 3 groups an increase in pest score for a given animal saw a decline in importance placed upon the animal's welfare. This relationship was strong for the general public but weak for conservationists and animal protectionists. Understanding aspects of potentially opposing viewpoints may be invaluable in supporting the development of new welfare-focused control methods.     

A new species of Jesogammarus from the Iki Island,Japan (Crustacea,Amphipoda, Anisogammaridae)

A new species of anisogammarid amphipod, Jesogammarus (Jesogammarus) ikiensis sp. n., is described from freshwaters in the Iki Island, Nagasaki Prefecture, Japan, based on results of morphological and molecular analyses. The new species is distinguished from all members of the genus by the combination of small number of setae on dorsal margins of pleonites 1–3, short and small number of setae on posterior margins of peduncular articles of antennae, mandibular article 1 without setae, well developed posterior lobes of accessory lobes of coxal gills on gnathopod 2 and pereopods 3–5, and pectinate setae on palmar margin of female gnathopod 2. A key to all the species of Jesogammarus is provided.     

中国海南奥利蛛属1新种（蜘蛛目：巨蟹蛛科）

本文报道了采自海南岛的巨蟹蛛科奥利蛛属Oliosl新种：指奥利蛛Oliosdigitatus sp．nov．。模式标本保存于河北大学博物馆。指奥利蛛,新种Oliosdigitatus sp．nov．（图1-4）正模♂,海南省昌江黎族自治县霸王岭镇,2009—5—25,张超采。副模2♂♂,海南省昌江黎族自治县霸王岭镇,2009—5—25,张超采。鉴别特征：在奥利蛛属Olios的种类中,本新种的生殖器官与Olios scalptor Jager＆Ono,2001非常相似,但具有以下特征可以区别：本新种雄蛛触肢器胫节突端半部指状;引导器半透明膜状,基部比端部厚,且基部具皱褶。词源学：以雄蛛触肢器胫节突的形状命名。地理分布：海南     

Species status and population genetic structure of the flightless chafer beetles Prodontria modesta and P. bicolorata (Coleoptera; Scarabaeidae) from South Island, New Zealand

This study uses isozyme electrophoresis to investigate the systematic status of two rare flightless chafer beetle species, Prodontria modesta and P. bicolorata , currently distinguished solely on the basis of colour. Seven polymorphic loci were analysed for the species in sympatry and allopatry. In sympatry, gene frequencies imply no genetic barrier between the two colour forms. Wright's hierarchical F-statistics were calculated to determine how the genetic variation is partitioned across the geographic range of the two species. Strong geographic structuring occurs at the population level but there is little genetic differentiation attributable to species. Comparisons of morphological measurements are in support of the electrophoretic results. The systematic significance of the two distinct colour forms is thus questionable. Under the biological, recognition or phylogenetic species concepts, the genetic data suggest that there is only one species, polytypic for a colour pattern. Most of the genetic diversity of this group of beetles lies within and among populations, which differ quite markedly over their geographic range, rather than between the two named species.     

Aspects of the biology of Xanthocnemis zealandica and Austrolestes colensonis (Odonata: Zygoptera) at three ponds in the South Island,New Zealand

Abstract

Both Xantnocnemis zealandica McLachlan and Austrolestes colensonis White were univoltine, and emerged asynchronously. At Woodend Pond, in 1971, larval growth was divided into cohorts by the drying up of some larval habitats in summer and autumn. Larval development was continuous in the other (permanent) habitats. A. colensonis differed from X. zealandica in its oviposition sites and its ability to survive the winter in the egg stage. There were differences in the larval food of the two species reflecting their differing agility.     

Stratigraphy of the fossil Chironomidae (Diptera) from Lake Grasmere,South Island,New Zealand,during the last 6000 years

The fossil chironomid fauna of a 3.26 m long sediment core from Lake Grasmere has been analysed. The fossil chironomid taxa belong mainly to the subgroups Tanytarsini, Orthocladiinae, Chironomini, and Tanyphodinae. Heptagyini and Podonominae were not common. Tanytarsini were the dominant component of the fauna with Corynocera sp. as the most abundant species during pre-Polynesian times (before 1000 yr BP). The abundance and the composition of the fossil chironomid taxa have fluctuated markedly over the last 6000 years. These fluctuations could be partly correlated with changes in the stratigraphy of the sediments in the core. Layers of highly minerogenic sediment contained the lowest numbers of remains whereas high abundances were found in the sections of the core with the greatest proportion of organic matter. It is suggested that major shifts in the structure of the chironomid community have been mainly caused by changes in the hydrology and inflows of the lake, and the rate and type of sedimentation, in addition to variations in lake productivity.     

A review of the genus Fallaciella (Bryopsida: Lembophyllaceae), including a new species from South Island,New Zealand

Abstract

An overview of the genus Fallaciella is provided, including reasons for its placement in the Lembophyllaceae. A new species, Fallaciella robusta sp. nov., is described from South Island, New Zealand. The differences between the two known species of Fallaciella are outlined and the main points summarized in a key. Illustrations are provided for both species, and a distribution map is provided for F. robusta.     

Desulfurella multipotens sp. nov., a new sulfur-respiring thermophilic eubacterium from Raoul Island (Kermadec archipelago,New Zealand)

A new moderately thermophilic sulfur-reducing eubacterium was isolated from bottom deposits of Green Lake (Raoul Island, Kermadec archipelago, New Zealand). Cells are short rods, 1.5–1.8 by 0.5–0.7 m, single or in pairs, motile with one polar flagellum, gram-negative with S-layer of subunit structure. Growth occurred between 42 and 77°C with the optimum at 58–60°C and at pH from 6.0 to 7.2 with the optimum at 6.4–6.8. The bacterium was obligately anaerobic and obligately sulfur-respiring, and capable of lithoautotrophic growth on a mineral medium with S° and H₂/CO₂ gas phase. In addition to molecular hydrogen, a wide range of substrates can be utilized as energy source in the presence of elemental sulfur: pyruvate, acetate, butyrate, pentadecanate, palmitate, stearate. Products are CO₂ and H₂S. The G+C content of DNA is 33.5 mol%. DNA-DNA homology with the type species of the genus Desulfurella — Desulfurella acetivorans — is 69±2%. A new species, Desulfurella multipotens sp. nov., with the type strain RH-8 is described.     

A new species of tusked weta from the Raukumara Range,North Island,New Zealand (Orthoptera: Anostostomatidae: Motuweta)

Abstract

A new species of weta from mainland New Zealand is described and assigned to the previously monotypic genus Motuweta Johns and the genus redefined. Mandibles of adult males bear prominent horns. Motuweta riparia n. sp. is a moderate‐sized species (36 mm) found on the margins of first or second order streams in the eastern mid North Island ranges. Its escape reaction is to leap into the stream and remain underwater until danger has passed, a strategy which has probably enabled it to survive in predator‐infested areas.     

Multilocus sequence analysis (MLSA) of ‘Rickettsiella costelytrae' and ‘Rickettsiella pyronotae’, intracellular bacterial entomopathogens from New Zealand

Aims

Larvae of scarab beetles live in the soil and are frequently hosts for microbial pathogens. In New Zealand, larvae of the grass grub, Costelytrae zealandica (Coleoptera: Scarabaeidae), and manuka beetles, Pyronota spp. (Coleoptera: Scarabaeidae), have been collected from field populations showing loss of vigour and a whitened appearance. Diagnosis indicated an intracellular infection of fat body tissues by Rickettsiella‐like micro‐organisms. Rickettsiella bacteria are under evaluation as a possible new source of insect bio‐control agents for important agricultural pests as, e.g. scarabaeid and elaterid larvae. The present study aimed at the unequivocal molecular taxonomic identification and comparison of the bacteria associated with Costelytra and Pyronota.

Methods and Results

Electron microscopy and phylogenetic reconstruction using a multilocus sequence analysis approach based on the 16S ribosomal RNA gene together with four protein‐encoding markers (ftsY, gidA, rpsA, and sucB) demonstrated that both bacteria from New Zealand are phylogenetically closely related, but not identical, and belong to the taxonomic genus Rickettsiella.

Conclusions

The bacteria under study should be referred to as pathotypes ‘Rickettsiella costelytrae’ and ‘Rickettsiella pyronotae’, respectively. Moreover, on the basis of the currently accepted systematic organization of the genus Rickettsiella, both pathotypes should be considered synonyms of the nomenclatural type species, Rickettsiella popilliae.

Significance and Impact of the Study

The study demonstrates that Rickettsiella bacteria are geographically widespread pathogens of scarabaeid larvae. Implications of the phylogenetic findings presented for the stability of host adaptation by Rickettsiella bacteria are critically discussed.