Movement, depth distribution and survival of spinetail devilrays (Mobula japanica) tagged and released from purse-seine catches in New Zealand

2016 ◽  
Vol 27 (1) ◽  
pp. 219-236 ◽  
Author(s):  
Malcolm P. Francis ◽  
Emma G. Jones
Keyword(s):  
New Zealand ◽  
Depth Distribution ◽  
Purse Seine ◽  
Mobula Japanica

Depth distribution of Recent deep‐sea benthic foraminifera east of New Zealand, and their potential for improving paleobathymetric assessments of Neogene microfaunas

2001 ◽  
Vol 44 (4) ◽  
pp. 555-587 ◽  
Author(s):  
Bruce W. Hayward ◽  
Rowan Carter ◽  
Hugh R. Grenfell ◽  
Jessica J. Hayward
Keyword(s):  
New Zealand ◽  
Benthic Foraminifera ◽  
Deep Sea ◽  
Depth Distribution

Influence of turbidity and fluctuating water levels on the abundance and depth distribution of small, benthic fish in New Zealand alpine lakes

2003 ◽  
Vol 12 (3) ◽  
pp. 216-227 ◽  
Author(s):  
D. Rowe ◽  
E. Graynoth ◽  
G. James ◽  
M. Taylor ◽  
L. Hawke
Keyword(s):  
New Zealand ◽  
Depth Distribution ◽  
Alpine Lakes ◽  
Water Levels ◽  
Benthic Fish

scholarly journals Hoki (Macruronus novaezelandiae) Diet Variability and  Associated Middle-Depth Demersal Fish Species Depth  Distribution in the Ecosystem on the Chatham Rise, New Zealand.

2021 ◽  
Author(s):  
◽  
Amelia MacLeod Connell
Keyword(s):  
Body Size ◽  
New Zealand ◽  
Fisheries Management ◽  
Species Distribution ◽  
Depth Distribution ◽  
Prey Species ◽  
Demersal Fish ◽  
Species Level ◽  
Geometric Constraints ◽  
Diet Variability

<p>Fisheries management in New Zealand is mostly on a single species basis. Globally there is a shift towards multispecies or ecosystem based fisheries management. For this to happen an understanding of how the ecosystem is organised and functions is needed. Trophic food web and diet studies have been used effectively to begin to understand the functioning of marine ecosystems. Who eats whom, however, is not the full extent of ecosystem function. Understanding of species distribution patterns, of both predators and prey species are also needed to begin to understand the full function of the marine ecosystem. The first part of this study investigated the diet of hoki (Macruronus novaezelandiae) over the Chatham Rise, New Zealand, between 200-800m. It characterised the diet of hoki as well as investigated potential sources of diet variability. Hoki diet was found to consist largely of mesopelagic teleosts, mainly of the family Myctophidae, natant decapods and euphausids, suggesting a pelagic feeding strategy, as other studies have also found. Differences were found in diet composition between this study and other studies on hoki diet, potentially suggesting differences in prey distribution between study areas. Differences in diet were found between fish from different depths and different sized fish from the same depth. No consistent pattern of diet differences was found between the different areas studied, suggesting that the patterns found may be aliasing depth and size patterns as well as reflecting differences in hoki size class distribution. The distribution of hoki was not homogeneous over the study area, with small fish found mainly in the western part of the study area in shallower water, while large fish were predominately found at greater depths over the whole study area. The second part of this study looked at the overall species distribution of 30 demersal fish species over the Chatham Rise, specifically examining for evidence of the mid-domain effect. The study also investigated body-size depth trends between these species, and split by class Osteichthyes and Chondrichthyes. The mid-domain effect predicts species richness, and thus distribution, is due to geometric constraints with the greatest species richness to be found at the centre of a geographically constrained domain. The overall species distribution was found to be explained by the mid-domain effect. The distribution pattern of larger individuals being found in deeper water, with smaller individuals found in shallower water has often been seen in marine systems. We found no interspecific pattern for body-size depth distribution with the entire species assemblage, nor when the assemblage was split by class into Osteichthyes and Chondrichthyes, which supports our findings of the mid-domain effect. At a species level patterns of positive, negative and no trend were found with body-size depth relationships. At a community level species distribution over the studied depth range was largely explained by the geometric constraints of the mid-domain effect, while at a species level distribution over depth was often a reflection of body size. Some species had large individuals deep while other species had small. Overall this supports the hypothesis that competition or adaptation works more strongly at a population or species level, than on the overall community who's species distribution can more often be attributed to random chance. This study begins to explain predator species distribution over the Chatham Rise and looks at the diet of one dominant species in the Chatham Rise ecosystem. This provides some of the basic knowledge needed for fisheries management to move towards a more ecosystem based approach. Further research should include investigation into prey species distribution and abundance to clarify some of the questions raised in the diet part of this study about the cause of diet variability and whether it was related to either prey abundance or patchy prey distribution. Research into the diet of other fish would be useful to ascertain which species compete with hoki for food and would provide fisheries managers with a list of species that may be affected indirectly through changes in hoki quota of abundance.</p>

scholarly journals Hoki (Macruronus novaezelandiae) Diet Variability and  Associated Middle-Depth Demersal Fish Species Depth  Distribution in the Ecosystem on the Chatham Rise, New Zealand.

2021 ◽  
Author(s):  
◽  
Amelia MacLeod Connell
Keyword(s):  
Body Size ◽  
New Zealand ◽  
Fisheries Management ◽  
Species Distribution ◽  
Depth Distribution ◽  
Prey Species ◽  
Demersal Fish ◽  
Species Level ◽  
Geometric Constraints ◽  
Diet Variability

<p>Fisheries management in New Zealand is mostly on a single species basis. Globally there is a shift towards multispecies or ecosystem based fisheries management. For this to happen an understanding of how the ecosystem is organised and functions is needed. Trophic food web and diet studies have been used effectively to begin to understand the functioning of marine ecosystems. Who eats whom, however, is not the full extent of ecosystem function. Understanding of species distribution patterns, of both predators and prey species are also needed to begin to understand the full function of the marine ecosystem. The first part of this study investigated the diet of hoki (Macruronus novaezelandiae) over the Chatham Rise, New Zealand, between 200-800m. It characterised the diet of hoki as well as investigated potential sources of diet variability. Hoki diet was found to consist largely of mesopelagic teleosts, mainly of the family Myctophidae, natant decapods and euphausids, suggesting a pelagic feeding strategy, as other studies have also found. Differences were found in diet composition between this study and other studies on hoki diet, potentially suggesting differences in prey distribution between study areas. Differences in diet were found between fish from different depths and different sized fish from the same depth. No consistent pattern of diet differences was found between the different areas studied, suggesting that the patterns found may be aliasing depth and size patterns as well as reflecting differences in hoki size class distribution. The distribution of hoki was not homogeneous over the study area, with small fish found mainly in the western part of the study area in shallower water, while large fish were predominately found at greater depths over the whole study area. The second part of this study looked at the overall species distribution of 30 demersal fish species over the Chatham Rise, specifically examining for evidence of the mid-domain effect. The study also investigated body-size depth trends between these species, and split by class Osteichthyes and Chondrichthyes. The mid-domain effect predicts species richness, and thus distribution, is due to geometric constraints with the greatest species richness to be found at the centre of a geographically constrained domain. The overall species distribution was found to be explained by the mid-domain effect. The distribution pattern of larger individuals being found in deeper water, with smaller individuals found in shallower water has often been seen in marine systems. We found no interspecific pattern for body-size depth distribution with the entire species assemblage, nor when the assemblage was split by class into Osteichthyes and Chondrichthyes, which supports our findings of the mid-domain effect. At a species level patterns of positive, negative and no trend were found with body-size depth relationships. At a community level species distribution over the studied depth range was largely explained by the geometric constraints of the mid-domain effect, while at a species level distribution over depth was often a reflection of body size. Some species had large individuals deep while other species had small. Overall this supports the hypothesis that competition or adaptation works more strongly at a population or species level, than on the overall community who's species distribution can more often be attributed to random chance. This study begins to explain predator species distribution over the Chatham Rise and looks at the diet of one dominant species in the Chatham Rise ecosystem. This provides some of the basic knowledge needed for fisheries management to move towards a more ecosystem based approach. Further research should include investigation into prey species distribution and abundance to clarify some of the questions raised in the diet part of this study about the cause of diet variability and whether it was related to either prey abundance or patchy prey distribution. Research into the diet of other fish would be useful to ascertain which species compete with hoki for food and would provide fisheries managers with a list of species that may be affected indirectly through changes in hoki quota of abundance.</p>

scholarly journals Nursery grounds of the orange roughy around New Zealand

2009 ◽  
Vol 66 (5) ◽  
pp. 871-885 ◽  
Author(s):  
M. R. Dunn ◽  
G. J. Rickard ◽  
P. J. H. Sutton ◽  
I. J. Doonan
Keyword(s):  
Life History ◽  
New Zealand ◽  
Deep Sea ◽  
Depth Distribution ◽  
Cold Water ◽  
Orange Roughy ◽  
Nursery Grounds ◽  
Recruitment Failure ◽  
Research Survey ◽  
Hoplostethus Atlanticus

Abstract Dunn, M. R., Rickard, G. J., Sutton, P. J. H., and Doonan, I. J. 2009. Nursery grounds of the orange roughy around New Zealand. – ICES Journal of Marine Science, 66: 871–885. The orange roughy (Hoplostethus atlanticus) is a deep-sea species with a centenarian lifespan, a life-history feature that may enable the stocks to withstand prolonged periods of recruitment failure. Most stocks have been substantially depleted, however, so estimating recruitment has become a priority in setting catch quotas to ensure future sustainability of the fisheries. A description of the nursery grounds of the species off New Zealand is provided, using extensive research-survey data from 12 541 bottom trawls and 713 midwater trawls. The juveniles were initially caught on the seabed, near known spawning grounds, and towards the shallower end of the species' distribution, and not in midwater or the shallower or deeper bottom tows. Densities were greatest at 850-900 m. As juveniles grew, their spatial and depth distribution expanded, both shallower and deeper, with a skew towards deeper water, such that by the onset of maturation, densities were relatively high in 850–1300 m of water. The early nursery grounds were in relatively warm water, but on the south Chatham Rise, appeared to be bounded by the presence of a cold-water front.

Growth rates of five species of subtidal clam on a beach in the South Island, New Zealand

1996 ◽  
Vol 47 (6) ◽  
pp. 773 ◽  
Author(s):  
HJ Cranfield ◽  
KP Michael ◽  
RICC Francis
Keyword(s):  
New Zealand ◽  
Computer Program ◽  
Growth Rates ◽  
Linear Growth ◽  
Depth Distribution ◽  
Surf Zone ◽  
Surf Clam ◽  
Incremental Growth ◽  
Linear Growth Model ◽  
Similar Growth

Growth rates of five species of New Zealand surf clams were estimated at Cloudy Bay, Marlborough, from analyses of sequential length-frequency samples with the computer program MULTIFAN and analyses of incremental growth of marked individuals with the computer program GROTAG. The von Bertalanffy parameters k and L∞ estimated by MULTIFAN were: Paphies donacina, 0.33 and 94.1; Spisula aequilatera, 1.01 and 60.3; Mactra murchisoni, 0.57 and 88; M. discors, 0.41 and 68; data for Dosinia anus could not be analysed reliably. These parameters estimated by GROTAG were: P. donacina, 0.35 and 84.8; S. aequilatera, 1.74 and 57.6; M. murchisoni, 0.58 and 80.6; M. discors, 0.54 and 61.5; D. anus, 0.36 and 61.6. The age-based growth estimated by MULTIFAN is not strictly comparable with the length-based growth estimated by GROTAG, but graphical comparisons show that both programs estimate similar growth rates for each species of surf clam. Interspecies differences in growth rates are hypothesized to be related to differences in species depth distribution within the surf zone. S. aequilatera, with the highest growth rate, is found just inshore of the primary wave break, where surf diatom abundance is postulated to be highest. An extension to the linear growth model of GROTAG that allows the predicted growth of larger animals to decline asymptotically to zero and never be negative is presented.

Magellanic Cloud Eclipsing Binaries: Primary Distance Indicators

1999 ◽  
Vol 190 ◽  
pp. 563-566
Author(s):  
J. D. Pritchard ◽  
W. Tobin ◽  
J. V. Clausen ◽  
E. F. Guinan ◽  
E. L. Fitzpatrick ◽  
...  
Keyword(s):  
New Zealand ◽  
Magellanic Cloud ◽  
Eclipsing Binaries ◽  
Fundamental Parameters ◽  
Distance Indicators

Our collaboration involves groups in Denmark, the U.S.A. Spain and of course New Zealand. Combining ground-based and satellite (IUEandHST) observations we aim to determine accurate and precise stellar fundamental parameters for the components of Magellanic Cloud Eclipsing Binaries as well as the distances to these systems and hence the parent galaxies themselves. This poster presents our latest progress.

Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

1970 ◽  
Vol 28 ◽  
pp. 106-107 ◽  
Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt
Keyword(s):  
New Zealand ◽  
General Hospital ◽  
Massachusetts General Hospital ◽  
Type I ◽  
Type Ii ◽  
Collaborative Effort ◽  
Temperature And Pressure ◽  
The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

Sign in / Sign up

Export Citation Format

Share Document