Effects of habitat and introduced mammalian predators on the breeding success of Yellow-eyed Penguins Megadyptes antipodes, South Island, New Zealand

1999 ◽  
Vol 5 (1) ◽  
pp. 16 ◽  
Author(s):  
Hiltrun Ratz ◽  
Brian Murphy
Keyword(s):  
New Zealand ◽  
Breeding Success ◽  
East Coast ◽  
Marked Effect ◽  
Forest Edge ◽  
Introduced Predators ◽  
Mammalian Predators ◽  
Predator Abundance ◽  
Breeding Seasons ◽  
Predator Guild

The endemic Yellow-eyed Penguin Megadyptes antipodes is threatened by habitat loss and introduced predators on mainland New Zealand. Nine colonies in the Catlins (south-east coast of South Island) were studied to measure breeding success, penguin abundance, and predator abundance in three successive breeding seasons (1991/92 to 1993/94). Nest numbers increased in all nine colonies in the three years despite predation (probably by Stoats Mustefa erminea) being the most important cause of breeding failure. Larger colonies with higher breeding success were in small gullies with limited shrubs and bushes rather than in the most intact mature forest colonies hitherto assumed to be optimal habitat for the birds. Penguin nests were concentrated near the forest edge, but predators were not, so the predation risk was not elevated near the forest edge. Fragmentation of the original forest habitat had no observable adverse effect on breeding success. Stoats dominated the predator guild, while Ferrets M. furo and Feral Cats Felis catus were rare. Trapping to kill predators early in the season had no marked effect on subsequent predation losses, but trapping intervention when a predation outbreak occurred curtailed further chick deaths. A simple population model predicts that Yellow-eyed Penguins populations will grow provided the average total chicks loss is less than 43% per season, or at least 0.85 chick per nest fledges each year. This requires predation losses to be less than 34%.

Colony growth and pup condition of the New Zealand fur seal (Arctocephalus forsteri) on the Kaikoura coastline compared with other east coast colonies

2006 ◽  
Vol 33 (6) ◽  
pp. 497 ◽  
Author(s):  
L. J. Boren ◽  
C. G. Muller ◽  
N. J. Gemmell
Keyword(s):  
New Zealand ◽  
Body Condition ◽  
East Coast ◽  
Colony Growth ◽  
The Body ◽  
Fur Seal ◽  
Seal Population ◽  
Condition Indices ◽  
New Zealand Fur Seal ◽  
Breeding Seasons

Abstract.Since its near extermination by sealing, the New Zealand fur seal (Arctocephalus forsteri) has been recolonising areas of its former range throughout New Zealand and Australia. This study examined fur seal population growth over four breeding seasons spanning 2002–05 at the Ohau Point and Lynch’s Reef colonies in Kaikoura and the Horseshoe Bay and Te Oka Bay colonies on Banks Peninsula, on the east coast of New Zealand. Estimates of pup numbers were made using mark–recapture techniques and condition indices were used to assess the body condition of pups in each colony. We found that the Ohau Point and Te Oka Bay colonies are growing exponentially (32% and 47% per annum respectively), reaching nearly 600 pups at Ohau Point and 300 pups at Te Oka Bay, whereas Horseshoe Bay appears stable. Pups born at Ohau Point are consistently heavier and in better condition than their Banks Peninsula counterparts despite the faster rate of growth observed at Te Oka Bay. An El Niño event in 2003 coincided with a drop in mass and condition at the Banks Peninsula colonies, but not at the Kaikoura colony. This discrepancy between colonies in response to environmental conditions suggests that colony-specific variables at Kaikoura may provide more favourable conditions for rearing pups than on Banks Peninsula.

scholarly journals New Zealand Falcon nests suffer lower predation in agricultural habitat than in natural habitat

2013 ◽  
Vol 23 (4) ◽  
pp. 512-519 ◽  
Author(s):  
SARA M. KROSS ◽  
PAUL G. McDONALD ◽  
XIMENA J. NELSON
Keyword(s):  
New Zealand ◽  
Natural Habitat ◽  
Habitat Type ◽  
Oceanic Islands ◽  
Artificial Nests ◽  
Video Footage ◽  
Introduced Predators ◽  
Agricultural Habitat ◽  
Mammalian Predators ◽  
The Hill

SummaryIntroduced mammalian predators have been implicated in the majority of avian extinctions on oceanic islands around the globe. Nowhere is this more apparent than in the decimated New Zealand avifauna, where introduced predators remain the primary threat to virtually all surviving endemic species, including the threatened New Zealand Falcon Falco novaeseelandiae. We used remote videography at falcon nests and conducted an artificial nest experiment to compare the rates of predation and responsible predators of falcons nesting in hills against those nesting in nearby commercial vineyards. Overall, 63% of artificial nests in the hills were predated, compared with 38% in vineyards. Further, artificial eggs were predated faster in the hills than those placed in vineyards. Video footage revealed that the suite of predators visiting real falcon nests was similar to those identified attacking artificial nests. However, predators differed across habitats, with nests in vineyards being predated mainly by hedgehogs Erinaceus europaeus and Australasian Harriers Circus approximans, whereas nests in the hill environments were mainly attacked by stoats Mustela erminea. These results demonstrate the important implications of habitat type on predation pressure associated with introduced predators. These may well prove a fruitful avenue of management if breeding can be fostered in safer areas, as in the case of this threatened falcon.

Differences in Susceptibility to Predation during Nesting Between Pied and Black Stilts (Himantopus spp.)

The Auk ◽  
1986 ◽  
Vol 103 (2) ◽  
pp. 273-280 ◽  
Author(s):  
Raymond J. Pierce
Keyword(s):  
New Zealand ◽  
Breeding Success ◽  
Site Fidelity ◽  
Indirect Evidence ◽  
Nesting Success ◽  
Nest Failure ◽  
Foraging Patterns ◽  
High Site ◽  
Breeding Seasons ◽  
The Impact

Abstract The nesting success of the Pied Stilt (Himantopus himantopus leucocephalus) and the endangered Black Stilt (H. novaezealandiae) was studied for three consecutive breeding seasons (1977-1979) in New Zealand. Black Stilts had a breeding success of less than 1%, compared with over 8% for Pied Stilts. Predation by feral mammals was the main cause of nest failure for both species, but the impact was greater on Black Stilts. Direct and indirect evidence (including trapping predators) suggests that these introduced ground predators kill many chicks. Several factors made Black Stilts vulnerable, particularly their nesting along stream banks that were often frequented by predators; Pied Stilts nested in swamps where predators were few. Black Stilt chicks took up to 2 weeks longer to fledge and their foraging patterns made them more vulnerable than Pied Stilt chicks. Other factors that possibly increased predation risk of Black Stilts include nesting at times of high predator activity, solitary nesting, high site fidelity, ineffective distraction displays, and lack of a disruptive camouflage pattern in adults. Introduced ground predators probably have contributed greatly to the decline of Black Stilts. Pied Stilts have not been affected similarly, because their evolutionary past has included long exposure to ground predators.

Control of introduced mammalian predators improves kaka Nestor meridionalis breeding success: reversing the decline of a threatened New Zealand parrot

2003 ◽  
Vol 110 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Ron Moorhouse ◽  
Terry Greene ◽  
Peter Dilks ◽  
Ralph Powlesland ◽  
Les Moran ◽  
...  
Keyword(s):  
New Zealand ◽  
Breeding Success ◽  
Mammalian Predators

Predation at Sooty Shearwater Puffinus griseus colonies on the New Zealand mainland: is there safety in numbers?

1999 ◽  
Vol 5 (4) ◽  
pp. 347 ◽  
Keyword(s):  
New Zealand ◽  
Conceptual Model ◽  
Breeding Success ◽  
Rattus Norvegicus ◽  
Breeding Birds ◽  
Breeding Failure ◽  
Safety In Numbers ◽  
Breeding Seasons ◽  
Norway Rats ◽  
Extinction Vortex

Burrow occupancy, survivorship, and breeding success were assessed at eight Sooty Shearwater Puffinus griseus colonies along the southeastern coast of New Zealand during the 1994/95 and 1995/96 breeding seasons. An average 46% and 47% of burrows contained breeding birds, but only three colonies had chicks survive to fledge. Most breeding failures were at the egg and early-chick phase. A large proportion of adults were killed at some places, causing the extinction of two of our study colonies. Predation by Stoats Mustefa erminea was the main cause of breeding failure and adult loss at most mainland colonies, but Norway Rats Rattus norvegicus were the principal predator at one colony. Protection of adults, eggs and young chicks from predators is crucial if mainland colonies are to persist. A conceptual model predicts that predation becomes part of the extinction vortex as the size of a colony dwindles because the depredations of a few rogue predators have catastrophic impacts on the few remaining birds.

scholarly journals Complete genomes of two extinct New Zealand passerines show responses to climate fluctuations but no evidence for genomic erosion prior to extinction

2019 ◽  
Vol 15 (9) ◽  
pp. 20190491 ◽  
Author(s):  
Nicolas Dussex ◽  
Johanna von Seth ◽  
Michael Knapp ◽  
Olga Kardailsky ◽  
Bruce C. Robertson ◽  
...  
Keyword(s):  
Climate Change ◽  
New Zealand ◽  
Human Impacts ◽  
Oceanic Islands ◽  
Genomic Diversity ◽  
Climate Fluctuations ◽  
Forest Clearing ◽  
Mammalian Predators ◽  
Demographic Trajectories ◽  
Human Climate

Human intervention, pre-human climate change (or a combination of both), as well as genetic effects, contribute to species extinctions. While many species from oceanic islands have gone extinct due to direct human impacts, the effects of pre-human climate change and human settlement on the genomic diversity of insular species and the role that loss of genomic diversity played in their extinctions remains largely unexplored. To address this question, we sequenced whole genomes of two extinct New Zealand passerines, the huia ( Heteralocha acutirostris ) and South Island kōkako ( Callaeas cinereus ). Both species showed similar demographic trajectories throughout the Pleistocene. However, the South Island kōkako continued to decline after the last glaciation, while the huia experienced some recovery. Moreover, there was no indication of inbreeding resulting from recent mating among closely related individuals in either species. This latter result indicates that population fragmentation associated with forest clearing by Maōri may not have been strong enough to lead to an increase in inbreeding and exposure to genomic erosion. While genomic erosion may not have directly contributed to their extinctions, further habitat fragmentation and the introduction of mammalian predators by Europeans may have been an important driver of extinction in huia and South Island kōkako.

Tectonic and paleoclimatic significance of Quaternary river terraces of the Waipaoa river, east coast, North Island, New Zealand

2000 ◽  
Vol 43 (2) ◽  
pp. 229-245 ◽  
Author(s):  
Kelvin Berryman ◽  
Michael Marden ◽  
Dennis Eden ◽  
Colin Mazengarb ◽  
Yoko Ota ◽  
...  
Keyword(s):  
New Zealand ◽  
East Coast ◽  
River Terraces ◽  
Paleoclimatic Significance

The Recent Cypraeidae of Northern New Zealand from the Kermadec Islands to the Poor Knights Islands, Southwest Pacific Ocean (Mollusca: Gastropoda: Cypraeidae)

The Festivus ◽  
2018 ◽  
Vol 50 (1) ◽  
pp. 36-54
Author(s):  
John Daughenbaugh
Keyword(s):  
New Zealand ◽  
Pacific Ocean ◽  
Continental Shelf ◽  
East Coast ◽  
Species Distributions ◽  
East Side ◽  
Tropical Eastern Pacific ◽  
The North ◽  
The Poor ◽  
Coastal Shelf

For researchers, isolated regions at the periphery of species’ distributions hold a peculiar fascination. The causes of their remoteness vary based on: distance (e.g. the Tropical Eastern Pacific), distance and countervailing currents (e.g. the Marquesas), location in a present day gyre (e.g. the Pitcairn Group) or the absence of present day means of veliger transport (e.g. the Vema Seamount). (Daughenbaugh & Beals 2013; Daughenbaugh 2015a & b, 2017). The northern New Zealand Region from the Kermadec Islands (Kermadecs) to the coastal and shelf areas in the northernmost part of New Zealand’s North Island (Northland), including the Poor Knights Islands (PKI), constitute the distributional boundaries for a number of Cypraeidae species. The boundaries are the result of the absence of coastal shelves along the east side of the Kermadec Ridge (Ridge) and precipitous drops to abyssal depths along Northland’s east coast continental shelf. Tropical waters, with their potential to transport Cypraeidae larvae, flow eastward from southern Queensland, Australia, entrained in the Tasman Front which terminates when reaching North Cape, the northernmost tip of Northland. There, the North Cape Eddy captures most of this flow while the remainder, the East Auckland Current (EAUC), flows intermittently southward along the eastern coastal, shelf and offshore areas of Northland into waters incapable of supporting Cypraeidae populations.

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