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1.
Zootaxa ; 5051(1): 7-10, 2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34810909

ABSTRACT

John Wells, who died at age 83 on 12 November 2018, was a research scientist, teacher, Professor of Zoology, Dean of Science at Victoria University of Wellington, New Zealand, family man and community leader. He was a man of his time, surviving World War II, progressing to a career that stretched around the world.


Subject(s)
Zoology , Animals , History, 20th Century , History, 21st Century , Male , Zoology/history
2.
J Fish Biol ; 96(1): 217-229, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31736078

ABSTRACT

Feeding habits of six deep-sea demersal trawl-caught macrourids on Chatham Rise, New Zealand, were examined from stomach contents during the austral summer. Three species were predominantly benthic foragers: smallbanded rattail Coelorinchus parvifasciatus on small epifaunal crustaceans, twosaddle rattail Coelorinchus biclinozonalis on epifaunal decapods and humpback rattail Coryphaenoides dossenus on benthic fishes and epifaunal decapods. Three species were predominantly benthopelagic foragers: banded rattail Coelorinchus fasciatus on hyperiid and gammarid amphipods and calanoid copepods, blackspot rattail Lucigadus nigromaculatus on small epifaunal crustaceans and suprabenthic mysids and Mahia rattail Coelorinchus matamua on epifaunal decapods and calanoid copepods. The most important predictors of diet variability were identified using distance-based linear models and included areal predictors in C. parvifasciatus, L. nigromaculatus and C. dossenus, fish size in C. dossenus, C. biclinozonalis and C. matamua, sample year in C. biclinozonalis and C. fasciatus and depth in C. matamua. Results are compared with previously published data for four other macrourid species from the same study area. The 10 grenadier species comprise benthic, benthopelagic and mesopelagic foraging guilds. This study brings the number of grenadier species for which diet on Chatham Rise has been described in detail to 12.


Subject(s)
Diet , Gadiformes/physiology , Amphipoda , Animals , Aquatic Organisms , Copepoda , Decapoda , Feeding Behavior , Fish Products , Fishes , Gastrointestinal Contents , New Zealand , Seasons
3.
Zootaxa ; 4565(3): zootaxa.4565.3.3, 2019 Mar 11.
Article in English | MEDLINE | ID: mdl-31716463

ABSTRACT

Azygokeras columbiae from Bute Inlet, British Columbia, Canada, is re-described, correcting some details and adding information not available in the original description. Azygokeras columbiae is unique amongst male Aetideidae in having the right antennule modified for grasping but without a true knee joint (geniculation) between segments XX and XXI nor a hiatus in the musculature at this joint, typical of taxa with a geniculate male antennule. Male Azygokeras have wide pivot points and arthrodial membranes between segments XXI and XXII, XXIII and XXIV and XXV and XXVI that allow greater movement in several planes than in homologous segments of Euaugaptilus and Heterorhabdus. Modifications of the terminal antennular joints allow for extensive movement in several planes associated with a series of short muscles in segments XIX to XXVI. These muscles become progressively more massive from proximal to distal on the antennule and are paired with an antagonistic muscle also increasing in mass distally.


Subject(s)
Copepoda , Animals , British Columbia , Male , Movement , Muscles
4.
Zootaxa ; 4229(1): zootaxa.4229.1.1, 2017 Feb 07.
Article in English | MEDLINE | ID: mdl-28187560

ABSTRACT

The Megacalanidae were revised based on new and archived material. Taxonomic confusion that has existed in the family is discussed and a method is suggested for stabilising names. A detailed examination of the morphology of this family, using the light microscope, has added further useful characters that distinguish genera and species. The added, hitherto undescribed species include character states incompatible with aspects of previous generic definitions (e.g. presence or absence of setae on the maxillule coxal endite). Nevertheless, the cladistic and molecular analyses confirmed that there are at least four monophyletic clades mostly with high bootstrap support. These clades represent already defined genera, one of which [Elenacalanus nom. nov. (nomen novum)] replaces the preoccupied name Heterocalanus Wolfenden, 1906. Four previously described species have been re-assigned to Elenacalanus in new combinations: E. princeps (Brady, 1883), E. eltaninae (Björnberg, 1968), E. sverdrupi (Johnson, 1958) and E. inflatus (Björnberg, 1968). Eleven new species are described: three Megacalanus, one Bradycalanus, six Bathycalanus, and one Elenacalanus nom. nov. Bradycalanus pseudotypicus enormis Björnberg, 1968 has been raised to species status based on genetic data although it can be only be distinguished morphologically from Br. typicus by its large size. All four genera are differentially diagnosed and keys are provided to the genera and species. We confirm that all male right antennules are geniculate in the Megacalanidae. Thirteen males are known. Of these males, eight are newly described (M. frosti n. sp., M. ericae n. sp., M. ohmani n. sp., Bathycalanus bradyi (Wolfenden, 1905a), Ba. dentatus n. sp., Ba. milleri n. sp., Ba. unicornis Björnberg, 1968, and Elenacalanus tageae n. sp.). We cannot be absolutely certain that the correct males have been assigned to the appropriate female so our decisions await testing with new data. The cladistic analysis provides the first morphology-based phylogeny. This scheme served as a working hypothesis which was tested and corroborated using the newly gathered molecular data. Vertical and horizontal distributions are summarised.


Subject(s)
Copepoda , Animals , Female , Male , Phylogeny
5.
J Anim Ecol ; 77(6): 1129-42, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18422559

ABSTRACT

1. Using 41 years of data, we examined annual variations in the reproductive performance of the red-billed gull at the Kaikoura Peninsula, New Zealand and related these to changes in climate, oceanography and the availability of the planktonic euphausiid Nyctiphanes australis, the bird's principal food. 2. In 1994 the population began to decline, and between 1983 and 2003 it was reduced by 51%. Adult non-breeders comprised an average of 32% of the population between 1983 and 1994, but following the decline they averaged only 18%. The age at recruitment changed markedly following the population decline: 27% of 2-year-old males bred for the first time prior to the decline, whereas the corresponding figure after the decline was 38%. The proportion of females commencing to breed as a 3-year-old was not significantly different before or after the decline. 3. An increase in the availability of euphausiids increased the likelihood of breeding and the recruitment of young individuals, caused earlier laying and resulted in an increase in the condition of adults, egg volume of gulls laying two egg clutches, clutch size and fledging success. 4. The relationship between food availability and the number of pairs that bred, laying date, clutch size and fledging success was significantly different prior to and after the population decline. The underlying cause appears to be a compensatory density-dependent mechanism that reduced interspecific competition for food. 5. The relative abundance of N. australis was correlated positively with the Southern Oscillation Index (SOI) and the frequency of occurrence of NE winds. The proportion of non-breeders and mean laying date were correlated negatively with the SOI, and mean egg volume of two egg clutches correlated positively with the SOI. 6. These results emphasize that availability of adult euphausiids is critical for red-billed gulls. We hypothesize that high primary productivity of inshore water near Kaikoura in winter, linked to a stable water column of coastal water and upwelling of additional dissolved inorganic nutrients, increases the availability of adult euphausiids to the red-billed gull as long as the coastal water is not replaced by offshore subtropical water intrusions of warmer, low-nutrient water.


Subject(s)
Charadriiformes/physiology , Climate , Feeding Behavior/physiology , Reproduction/physiology , Zooplankton/physiology , Animals , Female , Male , Population Dynamics , Seasons , Time Factors
6.
Environ Manage ; 39(1): 12-29, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17123004

ABSTRACT

We describe here the development of an ecosystem classification designed to underpin the conservation management of marine environments in the New Zealand region. The classification was defined using multivariate classification using explicit environmental layers chosen for their role in driving spatial variation in biologic patterns: depth, mean annual solar radiation, winter sea surface temperature, annual amplitude of sea surface temperature, spatial gradient of sea surface temperature, summer sea surface temperature anomaly, mean wave-induced orbital velocity at the seabed, tidal current velocity, and seabed slope. All variables were derived as gridded data layers at a resolution of 1 km. Variables were selected by assessing their degree of correlation with biologic distributions using separate data sets for demersal fish, benthic invertebrates, and chlorophyll-a. We developed a tuning procedure based on the Mantel test to refine the classification's discrimination of variation in biologic character. This was achieved by increasing the weighting of variables that play a dominant role and/or by transforming variables where this increased their correlation with biologic differences. We assessed the classification's ability to discriminate biologic variation using analysis of similarity. This indicated that the discrimination of biologic differences generally increased with increasing classification detail and varied for different taxonomic groups. Advantages of using a numeric approach compared with geographic-based (regionalisation) approaches include better representation of spatial patterns of variation and the ability to apply the classification at widely varying levels of detail. We expect this classification to provide a useful framework for a range of management applications, including providing frameworks for environmental monitoring and reporting and identifying representative areas for conservation.


Subject(s)
Classification/methods , Ecosystem , Environment Design , Marine Biology/classification , Conservation of Natural Resources , Environmental Monitoring , New Zealand , Oceans and Seas
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