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Introduction
The New Island
reserve and its projects, now with over 30 years of wildlife study and
conservation experience behind it, plays a leading role in the Falkland
Island's environmental protection efforts. The New Island Conservation
Trust operates the only purpose-designed site with established facilities
for field studies in the Falkland Islands. The legal status of New Island
as a research site is an important guarantee to the researchers who
come to work there. Long term research can be embarked upon with the
knowledge that projects are protected and will not be hindered by any
change in the property status.
The island's value
as a natural outdoor laboratory for environmental sciences, as well
as its size, provide us with the perfect base to concentrate on a direct
and more practical hands-on approach to nature conservation. As a permanent
study site a lot of our work concentrates on those species found in
this particular island environment. This is also expanded to look closely
at the island environment to see how changes may affect species ecology.
The influence of weather patterns, solar, temperature, rainfall and
the surrounding sea are important factors. The geological makeup, vegetation
and introduced species are also important aspects being studied.
This SW corner
of the Falkland archipelago is one of the best natural resources the
Falklands have. It is hoped, our work will assist in developing plans
for the management and conservation of this resource.
PhD student Riek Van Noordwijk from the
Netherlands working with King Cormorants
© G.Strange. 2007
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Biologists Paulo Catry and Ana Campos from
Portugal leg-banding a Thin Billed Prion chick
© G. Strange
. 2007
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CONSERVATION
CONCERNS
Offshore Fishing
The Falkland Islands
operate one of the largest offshore fisheries in the South Atlantic. The
fishery, which is operated largely by foreign registered fleets, is strictly
controlled by license and has a 200 mile offshore protection zone. The
Falkland Islands Government Fishery department has a good reputation for
its fish stock conservation management, but the very nature of this industry
and its volatile resource make predictions on stock levels difficult.
In the long term the question has to be asked, what will be the effect
of this industry on the large number of species which rely on this marine
resource for their survival.
©
I.J. Strange . 2006 |
Photo:
A fishing vessel in Falkland's waters is closely followed by hundreds
of Albatross - in addition to the possibility of a negative impact
on the fish stocks and subsequently the availability of food for
marine birds and mammals, Albatross are more directly vulnerable
to the effects of trawling and long-line fishing, often being fatally
caught up in the nets and hooks used by these vessels
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Black-browed Albatross Populations in the
Falkland Islands
Details, photos and paper coming
soon...for an outline of this information, please click
here to view some example pages from the current Management Plan
for New Island
Offshore Oil Exploration
Offshore Oil Exploration
has already been carried out in Falkland waters with this industry working
closely with the Falkland Islands Government on conservation issues.
Although there are no immediate indications that offshore oil exploration
will re-commence for some years, potential exploration areas such as
the Area of Special Co-operation which lies some 60 miles to the southwest
of New Island does present a need for special planning.
Its position in the main stream of the Falkland Current is an important
feeding ground for sea birds, especially penguins. Research by the New
Island Conservation Trust and University of Washington into the movements
of penguins at sea, can now confirm this. Being situated to the south
of the archipelago with the Falkland Current's flow moving north, the
vulnerability of the Islands to any mishap involving oil is also greatly
increased.
(For full details on the methodology and results
of this Rockhopper Penguin research, please see below: Scientific
Studies Carried Out 1997-2007)
Offshore Oil Exploration creates some
concernes for wildlife inhabiting coastal areas, such as these
Rockhopper Penguins
© I.J.
Strange . 2007
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INTRODUCTION TO SCIENTIFIC STUDIES
The Importance of New Island
New Island is an Important
Bird Area, hosting the largest seabird colony in the Falkland
Islands. This is the most important nesting site in the world for
the Thin-billed prion Pachyptila belcheri
(estimated population of 2 million pairs on New Island). Thousands
of the globally threatened Black-browed Albatross
Thalassarche melanophrys and Rockhopper
Penguin Eudyptes chrysocome also nest here, and regionally
important populations of several other globally threatened (White-chinned
Petrel Procellaria aequinoctialis) and near-threatened
species (Gentoo penguin Pygoscelis papua,
Magellanic penguin Spheniscus magellanicus
and Striated Caracara Phalcoboenus australis)
are also present, as well as one of the few South
American Furseal Arctocephalus australis colonies
found in the Falklands.
During the field
seasons September 2004 to March 2007, important research on Black-browed
Albatross, Rockhopper Penguins, Thin-Billed Prions, Upland Geese,
Falkland Skuas and invasive species such as the feral cat and the
Black Rat has been undertaken on the New Island South Reserve. In
the 2006/2007 season, much of this work was continued, with the addition
of new research on King Cormorants. In the 2007/08 season, commencing
in September 07, all of these projects will be continued, with the
Thin-billed Prion research reaching its 6th consecutive season.
With the Trust's
purchase of the northern half of New Island in 2006, our field work
can now be extended to cover the whole island. During the 06/07 season,
work was limited to basic census studies which will allow us to determine
numbers of certain breeding species on the north end of the island.
The New Island
Conservation Trust and its researchers periodically publish the results
of their research. To enable other researchers and interested web site
viewers to obtain a more detailed insight into this research we have
introduced a PDF file system into our web site. This system will enable
you to view some of the more recently published papers and pre publication
material related to the work of the New Island Trust.
Publication
of the New Island Management Plan - July 2007
From the end of July 2007, a new publication containing detailed information
about the New Island reserve, its conservation and scientific work,
history, flora and fauna and future management will be available. This
160 page, full colour book will cover every aspect of the island and
will include research and census project information, research strategy,
environmental management and conservation policies, future projects,
as well as photographs, example studies with results and wildlife distribution
maps. For a preview of this publication, please
click here
FACILITIES FOR SCIENTIFIC
STUDIES
The size of the
New Island South operation is an important consideration, this must
fit the island in the sense that field studies will not be invasive
or place undue pressure on sites or the species under study. Operations
must also take account of other essential elements of this site such
as water supplies. In this respect the facility will remain relatively
small, selective, independent and with a small administration, but maintaining
a high level of research.
The most significant
of the Trust's facilities is the Geoffrey C Hughes Field Station which
is named after its donor. The Field Station offers a large indoor workspace
equiped with areas for wet and dry laboratories, a computer work area,
library and herbarium, as well as fully self-contained accomodation
for up to 3 or 4 people.
SCIENTIFIC STUDIES CARRIED OUT: 1997 - 2007
Below is an outline
of some of the studied which have been conducted on New Island (south)
over the last 10 years. Many of our studies focus on long-term,
non-invasive investigations, thus resulting in a higher quality
of results, and a deeper understanding of the species involved.
If you would like any more information regarding any of our conservation
and scientific studies, please don't hestiate to contact us (details
on our Contact page).
NEW - More
information about our research projects below, including
census and research methodology, results and photographs, can be found
in the newly published 2007 New Island Management Plan, which is now
available. Please contact Ian
Strange for more information on how to obtain a copy.
2003-2007 (ongoing
research):
POPULATION DYNAMICS OF BLACK-BROWED ALBATROSS (Thalassarche
melanophrys)
Paulo Catry, Rafael Matias & Miguel
Lecoq
In 2003/04 we started a population dynamics and breeding ecology study
of Black-browed Albatrosses. Over 600 adult albatrosses have been
colour-banded and their fates, breeding success and survival are being
monitored on an annual basis. Preliminary results indicate that adult
survival is standard for the species and breeding success relatively
low. The collection of these data may help us understand why the albatross
population on New Island has been increasing, despite so many reports
of declining albatross populations worldwide.
At the same time, we are conducting a range of behavioural studies,
including comparative studies with albatrosses nesting on Bird Island,
South Georgia (in partnership with British Antarctic Survey, and also
with the support of individual researchers, namely Rafael Matias and
Miguel Lecoq).
In collaboration with Orea Anderson and Stuart Bearhop (Queen’s
University, Belfast) we are conducting a study on the feeding specializations
of individual albatrosses, to try to evaluate if some birds are more
at risk from accidental mortality in fishing gear than others.
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Photos:
Miguel Lecoq checking nests in a section
of the Black-browed Albatross study area; nests are tagged for
easy identification |
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2003-2007(ongoing research):
THIN-BILLED PRION (Pachyptila
belcheri) STUDIES -
An Introduction
Dr Petra Quillfeldt & Dr Juan F.Masello
Thin-billed prions are small procellariiform
seabirds of 140g, which are long-lived and lay a single egg per breeding
season. The excavate burrows, and both parents incubate between 46
and 47 days. Chicks hatch between the end December and mid January
and grow rapidly. They fledge at 47-61 days of age, depending on the
feeding rate.
We have studied provisioning rates and chick growth as well as hatching
and fledging success, in Thin-billed prions at New Island South since
2003 (e.g. Quillfeldt et al. 2003, Polar Biology 26, 746-752).
Photo
© Petra Quillfeldt . 2007 |
Photo
left:
A Thin-billed Prion chick, at 22 days old
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Sea surface temperatures during the study period were rising within
and between breeding seasons and were negatively correlated with provisioning
frequencies of thin-billed prions. Thus, periods of elevated sea surface
temperatures were associated with periods of low food availability
(Quillfeldt et al. submitted). Thin-billed prions, preying mainly
on amphipods, feed at the same trophic level as most commercially
caught fish and squid in the Falkland Islands, and data from the thin-billed
prions may therefore give insight in variations of resource availability
to the fish and squid populations. The data of thin-billed prion provisioning
rates suggest that the abundance of macrozooplankton, which provides
food for the commercially caught fish and squid, was low.
Seabirds are commonly used to monitor the productivity of their marine
environments, but different components of parental behaviour, offspring
mortality and offspring condition may not reflect environmental conditions
equally sensitively. Chick mass, feeding frequency data and begging
intensities, but not overall breeding success and fledging success
reflected food availability in the chick-rearing period adequately,
because most chicks survived to fledging despite poor provisioning
rates. The data suggests that due to the flexible growth rates of
chicks of pelagic seabirds, breeding success data may be insensitive
or even misleading and should be interpreted with caution. Instead,
we emphasize the usefulness of alternative non-invasive methods such
as the analysis of feeding rates from video and direct observations.
| Photo
right:
Dr Juan Masello and Dr Petra Quillfeldt preparing
to install a tiny camera into the burrow of a nesting Thin Billed
Prion. Using technology such as this, a new insight into these
birds behaviours can be obtained |
©
G. Strange . 2007
|
Thin-billed Prion Research
- Related publications:
. Quillfeldt, P.,
Strange, I.J. & Masello, J.F. (2007) Sea surface temperatures
and behavioral buffering capacity in Thin-billed prions: breeding
success, provisioning and chick begging. Journal of Avian Biology,
38. View
PDF
. Quillfeldt, P., Masello, J.F., Strange, I.J. & Buchanan, K.L.
(2006) Begging and provisioning of Thin-billed prions Pachyptila belcheri
is related to testosterone and corticosterone. Animal Behaviour, 71,
1359-1369. View
PDF
. Quillfeldt, P., Masello, J.F. & Strange, I.J. (2003) Breeding
biology of the Thin-billed prion Pachyptila belcheri at New Island,
Falkland Islands, in the poor season 2002/2003: Egg desertion, breeding
success and chick provisioning. Polar Biology, 26, 746-752. View
PDF
. Quillfeldt, P., Strange, I.J., Segelbacher,
G. & Masello, J.F. (in press) Male and female contributions to
provisioning rates of Thin-billed prions Pachyptila belcheri in the
South Atlantic. Journal of Ornithology. (No
PDF available)
Contributions to scientific conferences:
. Quillfeldt, P. & Masello, J.F. (2006)
When to fledge? The transition from burrow to sea in Thin-billed prions.
E-BIRD (European Science Foundation) Scientific Network on Adaptation
and constraints in avian reproduction: integrating ecology and endocrinology.
Final general workshop "Coping with environmental change: integrating
avian ecology and endocrinology". November 17-19, 2006. Glasgow,
UK.
. Quillfeldt, P. & Masello, J.F. (2006) Sex-differences in growth
and begging and their physiological basis. Speaker at the symposium
“Power and information: Conflict at the nest”, International
Ornithological Congress, Hamburg, Germany. Journal of Ornithology
147 (5, suppl. 1): 108 (abstract).
Manuscripts submitted / in revision:
. Poisbleau, M., Masello, J.F. & Quillfeldt,
P. (Resubmission pending) Acoustical parameters of begging call elements
of Thin-billed Prions vary between chicks, but convey little information
on chick condition.
. Quillfeldt, P., Dridi, S., Buyse, J. & Masello, J.F. (Resubmission
pending) Relationship between plasma leptin levels, begging and provisioning
in nestling Thin-billed prions Pachyptila belcheri.
. Quillfeldt, P., Ruiz, G., Aguilar Rivera, M. & Masello, J.F.
(submitted) Variability in leucocyte distributions and stress index
in Thin-billed prions Pachyptila belcheri during a poor season. Journal
of Ornithology.
. Quillfeldt, P., Poisbleau, M., Chastel, O. & Masello, J.F. (submitted)
Corticosterone in response to allostatic load in chicks of a pelagic
seabird: Diel rhythm, timing of fledging and nutritional stress in
the thin-billed prion Pachyptila belcheri. Naturwissenschaften.
2006-2007 (ongoing research)
ROCKHOPPER PENGUIN (Eudyptes chrysocome) STUDIES - An Introduction
Maud Poisbleau, assisted by Laurent Demongin
A detailed study following the complete
breeding cycle of Rockhopper penguins on New Island was commenced
at the start of the 2006 season by Maud Poisbleau with funding from
the Deutsche Forschungsgemeinschaft, Germany. This project is an ongoing
study, and will use new technologies for automated monitoring, featuring
a stationary weighbridge with an infra-red beam and antenna to read
transponders fitted to the penguins. Detailed data on the birds' attendance
and body condition is being collected and will contribute
to understanding how oceanographic conditions affect this species,
an important factor that may help determine the reason for the Rockhopper
penguin's population decline.
Recent research on New Island concluded that there are no important
land-based negative factors affecting the reproduction of Rockhopper
penguins on the reserve, and that these birds are only rarely predated
by non-native/invasive mammals (Matias 2005, Matias & Catry, unpublished).
Please see end of Scientific Research section at the bottom of this
page for more information on Invasive Species.
2005/06-2007 (ongoing research)
KING CORMORANT/BLUE EYED SHAG (Phalacrocorax atriceps albiventer)
STUDIES
- An Introduction
Riek van Noordwijk
A study on the breeding success of
this species was commenced in the season of 2005, by Dutch PhD student
Riek van Noordwijk. In the 2006 breeding season this study was extended
to include the use of time-depth and compass loggers in order to study
the inter-relationships between foraging and oceanographic conditions.
This research is to continue until 2009.
2005 - 2007 (ongoing research)
BREEDING AND DIET OF THE STRIATED CARACARA (Phalcoboenus australis)
ON NEW ISLAND
Paulo Catry & Miguel Lecoq
A detailed census
of the breeding population was carried out during the 2005/06 and
2006/07 breeding seasons. Furthermore, data on breeding success and
diet is being gathered for this little known and near-threatened bird
of prey. New Island is one of the most important nesting areas for
this species in the Falklands and throughout its global range.
2005/06 (ongoing research)
UPLAND GOOSE (Chloephaga picta leucoptera) STUDIES
Anja Gladbach & David Gladbach
Upland geese are abundant and widespread on New Island, with a high
breeding density. Preliminary studies looking at the effects of this
high breeding density on population parameters were commenced in the
breeding season of 2005/06, and will be continued in the 2007/08 season.
This study also includes banding young geese to monitor their movements
after fledging. Initial results have shown that young birds from New
Island have travelled to locations such as Port Stephens, 35 miles
away on the West Falkland mainland.
Related Documents:
. Quillfeldt, P., Strange, I.J. & Masello, J.F. (2005) Escape
decisions of incubating females and sex ratio of juveniles of the
Upland goose Chloephaga picta. Ardea, 93, 171-178. View
PDF - 2005
2004-2005: MIGRATION OF THE
FALKLAND SKUA (Catharacta skua antarctica) using Geolocators
Paulo
Catry
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Photo left:
A nesting Falkland Skua and chick
The migratory movements of the Falkland
skua have been, up until the present, completely unknown. In
2004/05 we retrieved some of the geolocators (Global Locator
Service sensors) we had deployed in the previous austral summer
season to study skua migration. |
While deployed
on birds, geolocators are permanently recording light intensity levels,
which allow us to calculate sunrise and sunset times, and hence latitude
and longitude values for the daily position of the birds. After the
end of the breeding season, the skuas we followed with GLS moved north
and northeast from the Falkland Islands and wintered over the Patagonian
Shelf and further offshore, a couple of thousand kilometres from the
breeding colonies. Like other skuas, they displayed a highly pelagic
behaviour in winter, rarely venturing close to the Falklands or the
South American coast.
1997-2004: SATELLITE TRACKING OF BREEDING
PENGUINS
- Rockhopper Penguin (Eudyptes
chrysocome)
- Magellanic Penguin (Spheniscus magellanicus)
- Gentoo Penguin (Pygoscelis papua)
This program involved the tracking of three species of penguin which
breed on the New Island reserve: Gentoo, Magellanic and Rockhopper
penguins. The project gathered valuable information on the foraging
and feeding grounds of these penguin species and showed the importance
of the Special Co-operation Area (an area licensed for future oil
exploration, lying between New Island and the Argentine coast) as
a major feeding ground for Rockhoppers during the breeding season.
Results also showed that some birds made trips almost as far as
the South American mainland (Boersma et al. 2002).
This was a
joint project operated by the New Island South Conservation Trust
and the University of Washington in Seattle USA, funded jointly
by the Falkland Islands Government, Pugh Foundation and the New
Island South Conservation Trust.
Full details of this study: View PDF Document
- 2002: (3.9MB)
Applying Ecology to Conservation:
Tracking Breeding Penguins at New Island South Reserve, Falkland
Islands: Boersma P.D., Stokes D.L. & Strange I.J. Aquatic Conservation
Vol 12 Number 1, Jan-Feb 2002. ISSN 1052-7613
Copyright 2002 John Wiley & Sons Ltd., Baffins Lane, Chichester,
West Sussex, PO19 1UD, Uk.
(Papers in this journal are available online ahead of the print
issue at www.interscience.wiley.com
)
CENSUS WORK
Selected Examples of Census studies carried out on New Island
South
2004, 2006, (1977-2007)
BLACK-BROWED ALBATROSS POPULATION CENSUS AT NEW ISLAND SOUTH,
SEPTEMBER 2004, SEPTEMBER 2006 AND POPULATION INCREASE TRENDS
FROM 1977-2007
Ian J. Strange
The Black-browed albatross Thalassarche
melanophrys is found all around the southern oceans between
25° and 60°S. The species was recently re-assessed and
given a conservation status of Endangered on the IUCN Red List
for 2004 (IUCN, 2004). Decreases in breeding populations have
been reported and are largely attributed to bycatch in long-line
fisheries (Croxall and Gales, 1998; Gales, 1998; Tickell, 2000;
Woehler et al., 2001). The Falkland Islands hold over 60% of the
global population and are the most important breeding site in
the world for this species. A 25% fall in population over the
last 20 years, at colonies in the Falkland Islands, has been reported
(IUCN, 2002).
The aim of the present study is to present results of recent surveys
of the population of Black-browed albatross at the New Island
South Nature Reserve in the West Falklands, together with a long-term
data set. Counts of adults returning to the colonies in late September-early
October were conducted in the field and from aerial photography.
Both methods gave comparable results.
Please
click here to download a PDF of this paper (extracted from the
New Island Management Plan 2007, Annex 5)
Strange
I.J., Black-Browed albatross (Thalassarche melanophrys) Population
Census at
New Island South, Falkland Islands. September-October 2004, September
2006 and Population Increase Trends from 1977 to 2007. New Island,
Falkland Islands - A South Atlantic Wildlife Sanctuary for Conservation
Management, July 2007. ISBN#978-0-9550708-1-3
Copyright I.J. Strange.
2005/06
CENSUS OF THE WHITE-CHINNED PETREL (Procellaria aequinoctialis)
IN THE FALKLAND ISLANDS
Paulo Catry & Miguel Lecoq (New Island)
This census
was carried out by Falkland Conservation and New Island Conservation
Trust in 2005/06. The Falklands population of the white-chinned
petrel is very small (less than one hundred pairs) and New Island
is one of two important nesting sites. A report was produced and
a paper is being prepared for publication.
1997-2006:
GENTOO PENGUIN (Pygoscelis papua)
CENSUS
Gentoo penguin numbers
on New Island have a long history of fluctuation. The first record
of the Island's Gentoo population is from 1933, when Government
naturalist, A.G. Bennett, conducted a census and obtained a result
of 2,500 nests. When the Island was taken over by Ian Strange in
1972, numbers were in the low hundreds, mainly due to past persecution.
Since the protection of the island, the general population trend
has shown an increase, however, total breeding failure in the 2002/03
breeding season, possibly caused by a harmful algal bloom known
as 'Red Tide', devastated New Island's population of Gentoo penguins.
The South reserve's population in the preceeding season of 2001
was recorded at 2,485 breeding pairs; in the following season adult
mortality, 0 breeding pairs and possible emmigration were observed.
In the 2003/04 breeding season, only 21% of the original 2,485 pairs
returned to breed, and further low-level mortality was recorded
in this season.
Censuses carried out in the subsequent breeding seasons have seen
the population slowly but steadily recovering, with 560 pairs counted
in 2006/07.
Full details of Census methodology and results for 1997-2001 Censuses:
View PDF Document - 2001:
(890KB)
Strange I.J., New Island South Conservation Trust:
Gentoo Penguin (Pygoscelis papua) Census. Penguin News, New Island
South Conservation Trust Supplement, October 12 2001.
Copyright New Island South Conservation Trust
1994-2004:
THIN-BILLED PRION (Pachyptila belcheri)
CENSUS
Some ten years research into this small ground
burrowing petrel has now been carried out. Studies have been made
of the general ecology and now scientists are carrying out more detailed
investigations of this species.
In the season of 2001- 2002 the first census of this species was carried
out resulting in a figure for an estimated population of four
million breeding adults. This figure is one of the most significant
to be confirmed on New Island, and makes the reserve one of the most
important breeding grounds in the world for this species.
Full details of this study:
View
PDF Document 1- 2002 (260KB)
1. Catry
P., Campos A., Segurado P., Silva M. & Strange I.J. 2002, Population
census and nesting habitat selection of Thin-Billed Prion Pachyptila
belcheri on New Island, Falkland Islands. Polar Biology 26: 202-207
Copyright Springer-Verlag 2003.
View
PDF Document 2
- 2003 (260KB)
2. Quillfeldt P.,
Masello J.F. & Strange I.J. 2003. Breeding biology of the Thin-Billed
Prion, Pachyptila belcheri, at New Island, Falkland Islands: Egg desertion,
breeding success, and chick provisioning in the poor season 2002/2003.
Polar Biology 26: 746-752
Copyright Springer-Verlag 2003. The original publication is available
at http://link.springer.de/
or at http://link.springer-ny.com.
1996-2001:
BLACK-BROWED ALBATROSS (Thalassarche melanophrys)
POPULATION CENSUS
October 2000: BLACK-BROWED ALBATROSS
- WEST CLIFFS POPULATION - AERIAL SURVEY
Full details
of these studies: View PDF Document - 2001: (2.2MB)
Strange I.J. 2001, Black Browed
Albatross, (Diomedea melanophris), Population Census, New Island
South. Penguin News, New Island South Conservation Trust Supplement
3, November 2, 2001.
Copyright New Island South Conservation Trust
 |
Photo left: The
view across the main Rockhopper Penguin and Black Browed Albatross
colony on New Island South
|
2000: ROCKHOPPER PENGUIN (Eudyptes chrysocome)
CENSUS
VIA ELECTRONIC COUNTER
Full
details of this Census: View PDF Document - 2001:
(1.5MB)
Strange I.J. 2001, Counting Rockhopper
Penguins Electronically: Settlement Colony, New Island South Reserve,
October 2000. Penguin News, New Island South Conservation Trust Supplement,
October 12, 2001.
Copyright New Island Conservation Trust
NON-NATIVE/INVASIVE
SPECIES
Rodent Control
The Black Rat (Rattus rattus) on the New Island South
Reserve
Like many of
the islands in the Falklands which have been exploited by man, New
Island is not free of rodents. Management since 1971 has placed a
lot of attention to the control of rodents. Based on the knowledge
and advice of New Zealand experts, studies are being carried out on
the reserve to assess the possibilities of carrying out a total eradication
program of the two species of rodent found on the island.
Scientific data has been collected on the Black rat (Rattus rattus)
and House Mouse (Mus musculus) using survey and index trap
lines covering the different environments on the reserve. Baiting,
disposal of potential sources of food by burning and general good
husbandry is ongoing. This is a project demonstrating that rodents
and the potential damage they may cause, can be reduced through good
management. This project is now in its fifth year.
|
Photo left:
The late Ingrid Schenk setting a trap line
for rodent control |
2004-2005/06
(ongoing research)
THE IMPACT OF INTRODUCED PREDATORS ON THE LOCAL BIRD POPULATIONS
Rafael Matias
Studies are being conducted to evaluate the
current impact that introduced mammals are having on the bird populations
nesting on New Island. Dietary studies, for example, have revealed
that although Thin-billed Prions are regularly killed and eaten by
feral cats, the predator preference goes for mammals such as cottontail
rabbits, rats and mice. The current direct impact of cats on Prions
seems to be low and they might even be having a positive role be keeping
the rodent populations low. Again, these results are preliminary.
2004-2005
DIET ANALYSIS OF THE BLACK RAT (Rattus rattus) USING STABLE
ISOTOPE RATIOS
Dr Petra Quillfeldt & Dr Juan F.
Masello
We will analyze isotope ratios of Black rat
(Rattus rattus) tissues, stomach contents and potential prey
items for trophic level (e.g. plants vs. birds) and prey origins (marine
vs. terrestrial). The data, together with rat trapping data, will
be used to assess the impact of these introduced rodents on the native
bird population, in particular the Thin-billed prions. This project
is carried out in co-operation with Dr. Rona McGill (Scottish Universities
Research & Reactor Centre) and Prof. Robert W. Furness (University
of Glasgow).
Introduced Mammals - Related documents:
. Catry, P., Silva, M.C., MacKay, S., Campos, A., Masello,
J., Quillfeldt, P. & Strange, I.J. (2006) Can thin-billed prions
Pachyptila belcheri breed successfully on an island with introduced
rats, mice and cats? The case of New Island, Falkland Islands. Polar
Biology. View
PDF - 2006 (please
note: copyright © Springer-Verlag 2006 - PDF for consultation
only).
Manuscripts in preparation:
. Introduced mammals coexist with seabirds
at New Island, Falkland Islands, I: Abundance of rodents and diet
of ship rats during the incubation period of Thin-billed Prions (Ingrid
Schenk, Ian J. Strange, Juan F. Masello, Petra Quillfeldt). View
PDF
. Introduced mammals coexist with seabirds at New Island, Falkland
Islands, II: Stable isotope analysis of the diet of introduced mammals
during the nestling period of Thin-billed prions (Petra Quillfeldt,
Ian J. Strange, Juan F. Masello, Anja Gladbach, Verena Roesch, Rona
A.R. McGill & Robert W. Furness). View
PDF
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