Growth, morphometrics and size structure of the Diadematidae sea urchin Centrostephanus rodgersii in northern New Zealand

The sea urchin Centrostephanus rodgersii has increased its range in Eastern Australia resulting in important ecological changes. C. rodgersii may also have expanded its distribution range to northern New Zealand in the last five to six decades, although little is known about this process and of the biology of the species in New Zealand. We investigated morphometrics as well as growth using two techniques (growth line count in genital plates and tag–recapture using the fluorescent marker tetracycline). These methods allowed modelling of size at age of C. rodgersii in New Zealand, which we compared with populations recently established in Tasmania. The modelled growth rate was only slightly higher in the New Zealand population, and no differences in morphometrics were observed. The New Zealand population structure suggests that annual recruitment occurs regularly, with the population including a range of ages (3 to 10+ years).

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Sea Urchins in the Saint Lawrence Estuary: Their Abundance, Size-Structure, and Suitability for Commercial Exploitation

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f83-066 ◽

1983 ◽

Vol 40 (4) ◽

pp. 474-486 ◽

Cited By ~ 34

Author(s):

John H. Himmelman ◽

Yves Lavergne ◽

Fritz Axelsen ◽

André Cardinal ◽

Edwin Bourget

Keyword(s):

Growth Rate ◽

Shallow Water ◽

Sea Urchin ◽

Size Structure ◽

Sea Urchins ◽

Strongylocentrotus Droebachiensis ◽

Lawrence Estuary ◽

Algal Abundance ◽

Ice Conditions ◽

Intermediate Size

Quantitative transects were made at nine locations along the Saint Lawrence Estuary, Québec, to examine changes in the abundance and size-structure of populations of the green sea urchin, Strongylocentrotus droebachiensis, in relation to the estuarine gradient. Near the seaward extremity of the estuary, sea urchin densities are very high and small urchins are particularly abundant in shallow water. In contrast, midway up the estuary, small urchins are scarce in shallow water, probably because they cannot tolerate the periodic drops in surface salinities which occur there. Where urchin densities are high, urchin grazing severely limits algal production, and because of low algal food availability, the urchin growth rate is exceedingly low. In the Upper Estuary, urchin numbers are low and no urchins are found near the surface. There is feeble recruitment of urchins, and the near absence of urchins of intermediate size suggests that there is a high probability that juveniles are killed before they reach intermediate size. The urchin growth rate is accelerated because of the abundance of algae present, and below 10 m deep some juveniles survive through the intermediate size range. After they reach 40–50 mm in diameter, they can move up to the 2- to 10-m-depth zone and can tolerate the periods of hypo-osmotic conditions which occur there. Suitable populations for commercial use are most likely found where salinity or winter ice conditions reduce urchin numbers to a level permitting greater algal abundance and an elevated somatic and gonadal growth of the remaining urchins.

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Linking population size structure, heat stress and bleaching responses in a subtropical endemic coral

Coral Reefs ◽

10.1007/s00338-021-02081-2 ◽

2021 ◽

Author(s):

Liam Lachs ◽

Brigitte Sommer ◽

James Cant ◽

Jessica M. Hodge ◽

Hamish A. Malcolm ◽

...

Keyword(s):

Heat Stress ◽

Size Structure ◽

Temporal Trends ◽

Early Recovery ◽

Size Frequency Distribution ◽

Frequency Distributions ◽

Community Organisation ◽

Size Frequency ◽

Eastern Australia

AbstractAnthropocene coral reefs are faced with increasingly severe marine heatwaves and mass coral bleaching mortality events. The ensuing demographic changes to coral assemblages can have long-term impacts on reef community organisation. Thus, understanding the dynamics of subtropical scleractinian coral populations is essential to predict their recovery or extinction post-disturbance. Here we present a 10-yr demographic assessment of a subtropical endemic coral, Pocillopora aliciae (Schmidt-Roach et al. in Zootaxa 3626:576–582, 2013) from the Solitary Islands Marine Park, eastern Australia, paired with long-term temperature records. These coral populations are regularly affected by storms, undergo seasonal thermal variability, and are increasingly impacted by severe marine heatwaves. We examined the demographic processes governing the persistence of these populations using inference from size-frequency distributions based on log-transformed planar area measurements of 7196 coral colonies. Specifically, the size-frequency distribution mean, coefficient of variation, skewness, kurtosis, and coral density were applied to describe population dynamics. Generalised Linear Mixed Effects Models were used to determine temporal trends and test demographic responses to heat stress. Temporal variation in size-frequency distributions revealed various population processes, from recruitment pulses and cohort growth, to bleaching impacts and temperature dependencies. Sporadic recruitment pulses likely support population persistence, illustrated in 2010 by strong positively skewed size-frequency distributions and the highest density of juvenile corals measured during the study. Increasing mean colony size over the following 6 yr indicates further cohort growth of these recruits. Severe heat stress in 2016 resulted in mass bleaching mortality and a 51% decline in coral density. Moderate heat stress in the following years was associated with suppressed P. aliciae recruitment and a lack of early recovery, marked by an exponential decrease of juvenile density (i.e. recruitment) with increasing heat stress. Here, population reliance on sporadic recruitment and susceptibility to heat stress underpin the vulnerability of subtropical coral assemblages to climate change.

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Temperature, salinity and growth rate dependences of Mg/Ca and Sr/Ca ratios of the skeleton of the sea urchin Paracentrotus lividus (Lamarck): an experimental approach

Marine Biology ◽

10.1007/s00227-010-1409-5 ◽

2010 ◽

Vol 157 (6) ◽

pp. 1293-1300 ◽

Cited By ~ 31

Author(s):

Julie Hermans ◽

Catherine Borremans ◽

Philippe Willenz ◽

Luc André ◽

Philippe Dubois

Keyword(s):

Growth Rate ◽

Sea Urchin ◽

Experimental Approach ◽

Paracentrotus Lividus

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Comparison of growth rate in culture, dry matter content, agar content and agar quality of two New Zealand red seaweeds,Gracilaria chilensis Bird, McLachlanet Oliveira andGracilaria truncata Kraft

Journal of Applied Phycology ◽

10.1007/bf02182425 ◽

1993 ◽

Vol 5 (1) ◽

pp. 85-91 ◽

Cited By ~ 10

Author(s):

T. D. Pickering ◽

V. H. Sladden ◽

R. H. Furneaux ◽

J. A. Hemmingson ◽

P. Redfearn

Keyword(s):

Growth Rate ◽

New Zealand ◽

Dry Matter ◽

Matter Content ◽

Dry Matter Content ◽

Red Seaweeds ◽

Gracilaria Chilensis ◽

Agar Quality

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Fetal Cephalometry During Normal Pregnancy in a New Zealand Population

Australian and New Zealand Journal of Obstetrics and Gynaecology ◽

10.1111/j.1479-828x.1976.tb02589.x ◽

1976 ◽

Vol 16 (4) ◽

pp. 210-212 ◽

Cited By ~ 8

Author(s):

D. R. Aickin ◽

W. R. Chatfield ◽

P. E. Rippon

Keyword(s):

New Zealand ◽

Normal Pregnancy ◽

Zealand Population

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Melampsora medusae. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400480 ◽

1975 ◽

Author(s):

J. Walker

Keyword(s):

New Zealand ◽

Geographical Distribution ◽

Northern Hemisphere ◽

Populus Deltoides ◽

Leaf Damage ◽

Main Method ◽

Melampsora Medusae ◽

Nursery Stock ◽

Eastern Australia ◽

Incremental Growth

Abstract A description is provided for Melampsora medusae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Pycnia and aecia on Coniferae, especially Larix and Pseudotsuga, less commonly on Pinus and other genera (Ziller, 1965). Uredinia and telia on species of Populus, especially Populus deltoides, and its varieties and hybrids P. balsamifera, P. nigra var. italica and others. Its exact host range on species of Populus is not known due to confusion with other species of Melampsora and to uncertainty in the reported identity of some species of Populus and clones (Walker, Hartigan & Bertus, 1974). DISEASE: Leaf rust of poplars, causing severe leaf damage and early defoliation on susceptible species and clones. Continued defoliation of successive flushes of growth predisposes trees to winter injury and dieback (Peace, 1962) and can cause death of trees, especially nursery stock and trees 1-2 yr old (25, 204; 47, 241; Walker Haitigan & Bertus, 1974). Reduction in incremental growth of timber occurs with susceptible varieties. Some damage can occur to the conifer hosts. It is often severe on Pseudotsuga menziesii (45, 459; 47, 126) and in nurseries Pinus spp. and Larix spp. can be heavily attacked (Ziller, 1965). GEOGRAPHICAL DISTRIBUTION: North America (Canada, USA), Asia (Japan); Australasia and Oceania (Australia, New Zealand); Europe (France, Spain). Reports of Melampsora spp. on poplars (including P. deltoides and P. canadensis) from South America (Argentina, 21, 173), Uruguay (Lindquist & de Rosengurtt, 1967) may refer in part to M. medusae. TRANSMISSION: By air-borne urediniospores, often over long distances (suspected from eastern Australia to New Zealand). Urediniospores survive the winter in milder climates on semi-evergreen lines and on green sucker growth of deciduous trees. This is probably the main method of overwintering in the Southern Hemisphere and in warmer parts of the Northern Hemisphere. The possibility of bud carryover as occurs with M. epitea on Salix in Iceland (Jorstad, 1951) and the Canadian Arctic (Savile, 1972) should be investigated. Telia survive the winter and basidiospores formed in spring infect susceptible conifers in parts of the Northern Hemisphere (Ziller, 1965) but no conifer infection has so far been found in Australia.

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Senecio lautus complex in Australia. I. Taxonomic considerations and discussion of some of the related taxa from New Zealand

Australian Journal of Botany ◽

10.1071/bt9640282 ◽

1964 ◽

Vol 12 (2) ◽

pp. 282 ◽

Cited By ~ 10

Author(s):

SI Ali

Keyword(s):

New Zealand ◽

Zealand Population ◽

The Status ◽

First Time

Reasons for the retention of the name Senecio lautus Forst. f. ex Willd. for both New Zealand and Australian forms are advanced. It is concluded that the New Zealand population should be given the status of a subspecies. Synonymy of S. lautus subsp. lautus and typification of various names involved are discussed. S. glaucophyllus subsp. discoideus (T. Kirk) Ornd. is reported for the first time from Tasmania.

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A new species of sea urchin associating clingfish of the genus Dellichthys from New Zealand (Teleostei, Gobiesocidae)

ZooKeys ◽

10.3897/zookeys.740.22712 ◽

2018 ◽

Vol 740 ◽

pp. 77-95 ◽

Cited By ~ 4

Author(s):

Kevin W. Conway ◽

Andrew L. Stewart ◽

Adam P. Summers

Keyword(s):

New Species ◽

New Zealand ◽

Sexual Dimorphism ◽

Sea Urchin ◽

Coastal Waters ◽

Sensory System ◽

A New Species ◽

Shallow Coastal Waters

A new species of clingfish, Dellichthystrnskii sp. n. is described on the basis of 27 specimens, 11.9–46.0 mm SL, collected from intertidal and shallow coastal waters of New Zealand. It is distinguished from its only congener, D.morelandi Briggs, 1955 by characters of the cephalic sensory system and oral jaws, snout shape, and colouration in life. A rediagnosis is provided for D.morelandi, which is shown to exhibit sexual dimorphism in snout shape.

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