The decline of Falkland Islands penguins
in the presence
of a commercial fishing industry
by Mike Bingham - Published 2002 in Revista Chilena de
Historia Natural 75: 805-818.
The Falkland Islands are an important breeding site for three
species of penguin, Gentoo (Pygoscelis papua), Southern Rockhopper
(Eudyptes c. chrysocome) and Magellanic penguin (Spheniscus magellanicus).
The total penguin population for the Falkland Islands has declined
by 84% during the 1980s and 1990s. These declines did not occur
in coastal South America, so potential causes of decline in the
Falklands have been investigated.
The suspected cause of decline is a reduction of fish and squid
due to large-scale commercial fishing around the Falklands. Since
1995 Rockhopper and Gentoo populations have ceased declining, and
appear to have reached a new equilibrium, albeit at a much lower
level than before commercial fishing began. This has been matched
by improved chick-rearing success and juvenile survival, however
Magellanic penguins continue declining in the Falklands. Diet analysis
shows that Magellanic penguins have a greater reliance on squid
and fish species being taken commercially.
In 1998 drilling for oil began around the Falklands, despite warnings
that environmental protection was inadequate. Within a month the
first of three separate oil spills occurred, killing and contaminating
hundreds of penguins. The oil rig completed its drilling operations
after five months and left the Falklands. Since then no further
oil spills have occurred. Oil exploration is due to recommence in
the near future, and environmental safeguards have not been improved.
Ecotourism has increased rapidly over recent years in the Falklands,
with penguins being the main attraction. Monitoring of the affects
of tourism has concentrated on breeding success and population change,
and the results indicate no detrimental affects on penguin populations
at the current level.
This paper investigates potential causes of penguin decline in
the Falkland Islands, drawing comparison with populations in Chile
which appear to be healthy. It concludes by calling on the Falkland
Islands Government to exclude large-scale commercial fishing close
to penguin breeding sites.
Las islas Falklands es un lugar importante para tres especies
de pingüinos, pingüino papua (Pygoscelis papua), pingüino de penacho
amarillo (Eudyptes c.chrysocome) y pingüino de Magallanes (Spheniscus
magallanicus). Recientemente estas especies han disminuido 84% en
estas islas. En la costa de sudamerica los pingüinos no disminuyeron.
La razon sospechada es un reducción de peces y calamares debido
a los barcos de pesca comercial en las aguas de las islas Falklands.
En 1995 el pingüino papua y el pingüino penacho amarillo terminaron
sus disminuciones y ya parece que sus poblaciones están en equilibrio,
pero en un número mucho mas bajo que antes que los pescadores comenzaron
20 años atras. Todavía el pingüino de Magallanes disminuye en las
islas Falklands. El pingüino de Magallanes tiene mas dependencia
de species de calamar y pescado utilizado por barcos de pesca comercial.
En 1998 comenzaron exploraciones petroleras en las islas Falklands,
a pesar de avisos de protección por la fauna no fue suficiente.
Tres derrames de petróleo ocurrieron en cinco meses, y cientos de
pingüinos murieron. La torre de perforación se fue despues de cinco
meses, y no ocurrieron más derrames de petróleo. Nuevamente van
a comenzar a buscar petróleo, sin mejorar la protección para la
El turismo ha crecido rápidamente en las islas Falklands, y la
mayoria de los turistas llegan para ver los pingüinos. Investigaciones
de poblaciones y éxito reproductivo indican que aún no hay efectos
perjudiciales para los pingüinos por esta actividad.
Este reportaje investiga la disminución de pingüinos en las islas
Falklands, y hace compariciones con poblaciones en Chile que parecen
The Falkland Islands lie in the south-west Atlantic, 450km north
east of the southern tip of South America. The archipelago is made
up of over 700 hundred islands, comprising a total land area of
over 12,000 sq km. The irregular shape and large number of islands,
gives the Falklands a very long coastline in relation to its land
area, providing a wide variety of coastal habitats. This varied
habitat, combined with the productive waters of the Patagonian shelf,
make the Falklands a good place for seabird reproduction and feeding,
especially for albatross, cormorants and penguins.
Five species of penguin breed in the Falkland Islands - King penguin
(Aptenodytes patagonicus, Miller 1778), Gentoo penguin (Pygoscelis
papua, Forster 1781), Southern Rockhopper penguin (Eudyptes c. chrysocome,
Forster 1781), Macaroni penguin (Eudyptes chrysolophus, Brandt 1837)
and Magellanic penguin (Spheniscus magellanicus, Forster 1781).
During the 1980s and early 1990s populations of Gentoo, Southern
Rockhopper and Magellanic penguins declined dramatically in the
A lack of comparative data made it impossible to determine whether
such declines were part of a regional trend, or whether they were
due to circumstances pertaining to the Falklands. There was also
a lack of basic research data with which to determine the extent
to which human activities (such as commercial fishing, tourism,
oil exploration and removal of eggs for human consumption) were
contributing to the decline. Since the late 1980s, penguin populations
around the Falklands have been studied in order to address these
issues. This paper looks at the evidence of population decline in
the Falklands, and investigates the role of human activities, using
comparative data from South America.
MATERIALS & METHODS
In the austral summer of 1995/96, an island-wide penguin census
of the Falkland Islands was conducted. All species were counted
except for the Magellanic penguin, which was not included because
of the difficulties of conducting a census on a species that nests
For Gentoo and Rockhopper penguins, nest counts were made to determine
the number of breeding pairs. Counts were timed to correspond with
the end of the egg laying period, thereby ensuring that few pairs
were still to lay, and allowing an assessment to be made of the
underestimate due to pairs failing, by using failure rates during
incubation from other studies.
Gentoo penguins concluded their first egg-laying by the end of
October 1995. The 1995/96 census counted 15% of the Gentoo population
between 15th and 31st October, and the remainder between 1st November
and 1st December. Because Gentoos failing early tend to re-lay,
and failure rates during incubation are low (c. 1% per week), the
magnitude of any underestimates resulting from differences in survey
dates should be well below 5%.
Rockhopper penguins are much more synchronous in terms of egg-laying
than Gentoo penguins. Laying was concluded by mid-November 1995,
and the 1995/96 census counted 98% of the Rockhopper population
between 1st November and 1st December (2% between 2nd and 18th December).
Repeated counts of Rockhopper colonies in previous years showed
that nest counts drop at a rate of about 3% per week for the first
month after egg-laying, as a result of failed nests. It is therefore
unlikely that the average underestimate of Rockhopper population
For most Rockhopper and all Gentoo breeding sites, the recorder
made two separate counts of all occupied nests using a tally counter.
The mean of the two counts was taken as the number of breeding pairs.
Where these counts differed by more than 10%, a third count was
taken to give a mean of three counts. In practice this was rarely
necessary, and the spread of results was usually well within plus
or minus 5%.
For the very large Rockhopper colonies on Steeple Jason, Grand
Jason, Bird Island and Beauchene Island, direct ground counts were
not possible. These sites were counted using a total of 60 randomly
selected sample plots to determine the range of nesting densities,
and the areas of the colonies were determined to enable estimates
of total breeding pairs. A minimum of 10% and a maximum of 15% of
the total colony area was sampled at each of the sites. These measurements
of area and density taken during the site visits were later compared
against aerial photographs taken of the colonies. The margin of
error for this methodology is greater than for direct counts, but
should be within plus or minus 10%.
The breeding cycle of the King penguin is different from that
of Gentoos and Rockhoppers, with chicks over-wintering at the colony,
and a complete breeding cycle lasting over a year. This tends to
result in individual birds having their following breeding cycle
out of phase with its predecessor; thus large chicks and eggs both
occur in a colony at the same time. This complicates assessment
of breeding pairs, so chick counts were taken instead. The estimation
of error for chick counts is well below 5%, but will under estimate
the number of breeding pairs by about 20% (Lewis Smith & Tallowin,
Between 1989 and 2002, a total of 40 breeding sites (one King,
21 Gentoo, 8 Rockhopper and 10 Magellanic) were counted annually
in the Falklands to determine changes in population size. For King,
Gentoo and Rockhopper penguins these counts were conducted as described
above. Because Magellanic penguins nest in burrows in the Falklands,
nest counts were conducted by examining each burrow within the colony
for signs of nest occupation and breeding activity. For difficult
burrows the use of a video camera on a long pole was employed to
determine the presence of an active nest. Each burrow occupied by
a breeding pair was marked with a small spot of paint during the
count to prevent double-counting.
Annual chick counts were also made at each of the study sites
prior to fledging, in order to determine annual breeding success.
Breeding success was determined by conducting nest counts within
the colony at the onset of incubation, as described above. Each
colony was then revisited just prior to fledging, and all chicks
within the colony were counted. Two counts were made using a tally
counter, with a third count being made where the first two results
differed by more than 10%. Breeding success was taken as the mean
number of chicks recorded within the colony divided by the mean
number of occupied nests recorded at the start of the season (chicks
per breeding pair).
For Magellanic penguins around 250 occupied burrows were also
marked with names or numbers, and visited an average of three times
per week from October to March, in order to record egg/chick progress
and to determine the causes of egg/chick loss. Eggs that failed
to hatch were later examined to determine the stage of embryo development,
and dead chicks were removed from the burrows for measuring and
weighing, and to assess the causes of death where possible. Fledglings
were weighed prior to departure from the colony, by suspending birds
from a spring balance using a soft cotton loop around the legs.
Some adults were marked in their burrows using red and blue animal
marker crayons on long poles, so that each partner could be identified
during hourly observations. These markings were placed on the throat
where they were easily visible during nest inspections, and where
they could not be easily removed during preening. Hourly observations
recorded time spent in and away from the burrow for each partner
during incubation and chick rearing.
In addition to monitoring overall population trends and breeding
success, comparisons were made to determine the effects of human
activity in the Falklands. Population trends and breeding success
were compared for colonies which are actively promoted by the Falkland
Islands Tourist Board as official tourist destinations, and for
colonies which are not visited by any tourists, in order to investigate
the impacts of tourism. The Falkland Islands Government also permits
the removal of Gentoo penguin eggs for human consumption. Unlike
most other penguins, Gentoos will readily re-lay after loosing their
clutch, leading to claims by farmers that the removal of eggs does
not harm the species. Comparisons of population trends and breeding
success were made for colonies where eggs are harvested for human
consumption, and for colonies from which no eggs are taken, in order
to evaluate the impact of egging.
Each year diet samples were taken of Gentoo, Rockhopper and Magellanic
penguins using the stomach-flushing technique described in Wilson
(1984). Samples were taken during incubation and chick-rearing,
from adults returning to the colony after foraging. Samples sizes
varied from year to year, but average around 25 individuals per
year for each species.
Stomach samples were drained and stored in jars with formaline
solution or alcohol, ready for later examination. Once in the laboratory
the stomach samples were rinsed with water, drained to remove any
excess liquid, and weighed to determine the wet weight of food retrieved.
Each sample was then divided up into its appropriate components,
which were weighed individually to determine proportional dietary
composition by wet weight. Fish otoliths, cephalopod beaks and crustacean
carapaces (which are not easily digested) were used to aid species
identification, and to estimate proportional composition. These
data were then compared with fisheries catch statistics in order
to determine the level of overlap between penguin diet and commercial
fishing activities (Falkland Islands Government 2001).
From 1998 diet sample analysis in the Falklands was taken over
by Dr A. Clausen of Falklands Conservation (Clausen 2000), although
the methodology remained unchanged (Wilson 1984).
During the austral summer of 1996/97, a penguin census was conducted
in South America, in order to determine whether penguin declines
in the Falklands had occurred elsewhere. It had been shown during
the 1995/96 census of the Falkland Islands that it requires little
extra effort to count all penguin species during the course of such
a census. The only exception was the Magellanic penguin. Its widespread,
low-density distribution in burrows made it impossible to census
with methods employed for surface nesting species. For this reason
it was decided that the 1996/97 census would include all South American
penguins, except for those of the Genus Spheniscus.
During the 1995/96 Falkland Islands census it had been possible
to conduct ground counts of incubating pairs at each of the breeding
colonies, because most colonies were relatively accessible. By contrast,
many of the South American colonies are remote and inaccessible,
and any attempt to conduct ground counts of each and every colony
would have been doomed to failure. It was therefore decided from
the outset that the census would be conducted by light aircraft,
thereby negating the need to get ashore at difficult and remote
The location of all the Falkland Islands breeding sites had been
known prior to the commencement of the 1995/96 census, but this
was certainly not the case for South America. Although data did
exist for a number of known breeding sites around South America
(Frere et al. 1993, Venegas 1984, 1991, Woehler 1993), it was likely
that other sites existed which had not been previously recorded.
This was another reason for favouring an aerial census, since it
provided the opportunity to cover large areas of suitable coastline
in search of previously unrecorded colonies. This reduced the margin
of error that would otherwise have arisen from new sites being overlooked,
however the margin of error for aerial counts was higher than for
In order to quantify the margin of error likely to be expected
from aerial counts, a number of aerial censuses were made of Rockhopper
colonies in the Falkland Islands for which the number of breeding
pairs was also determined by ground counts. These aerial counts
differed by a maximum of 14% from ground counts made of the same
colony, giving a total margin of error of +/- 20% for aerial census
The 1996/97 aerial census was conducted throughout the known Eudyptes
breeding ranges of Chile and Tierra del Fuego. The Atlantic coast
of mainland Argentina was excluded from the census, since this coastline
has been well studied, and does not hold any breeding sites for
species covered by the census, except for a very small Rockhopper
colony on Isla Pingüino, near Puerto Deseado (Frere et al. 1993).
This colony is regularly monitored as part of an ongoing research
programme, and population data from their research was used in favour
of duplicating results.
Since 1997 the annual monitoring of Magellanic penguins has been
extended to include colonies in southern Chile, in order to compare
annual population trends, breeding success, foraging behaviour and
diet composition between the Falkland Islands and Chile.
The 1995/96 Falkland Islands census recorded 65,000 breeding pairs
of Gentoo penguins at 81 breeding sites. This represents a decline
of around 45% since the early 1980s (Croxall et al. 1984). A repeat
census by Falklands Conservation in 2000/01 (Clausen 2001) shows
a population recovery to around 113,000 breeding pairs, equivalent
to about 35% of the world population, last estimated at 320,000
breeding pairs (Woehler 1993).
The 1995/96 Falkland Islands census recorded 297,000 breeding
pairs of Southern Rockhopper at 36 breeding sites. This represents
an 88% decline since the early 1980s (Croxall et al. 1984). A repeat
census by Falklands Conservation in 2000/01 (Clausen 2001) recorded
a population of 272,000 breeding pairs. The current Falklands population
represents about 60% of the world population, with the remaining
40% located at 15 breeding sites in Chile and Argentina (Bingham
& Mejias 1999).
Although an island-wide census has never been conducted for Magellanic
penguins, annual counts since 1989/90 indicate that Magellanic penguins
have undergone a 76% decline in the Falklands between 1989/90 and
2001/02. No data exists prior to 1989/90, but since Gentoo and Rockhopper
penguins underwent their greatest declines during the 1980s, it
is likely that the overall decline of Magellanic penguins is much
greater than the 76% recorded. Unlike Gentoo and Rockhopper penguins,
Magellanic penguins are still declining.
Gentoo penguins have averaged 0.84 chicks per breeding pair since
studies began in 1990/91 (n = 12, S.D.= 0.21). Prior to 1993/94
the average was 0.73 chicks per breeding pair, but between 1993/94
and 1999/2000 the average increased to 0.99 chicks per breeding
pair. A Mann-Whitney U test showed this difference to be significant
at the 5% level. Gentoo populations stopped declining around 1993/94,
and by 2000/01 they had recovered to their pre-fisheries level of
around 115,000 breeding pairs (Croxall et al. 1984, Bennett 1933).
Since then breeding success has slumped to an average of only 0.59
chicks per breeding pair, with the last two seasons data showing
the lowest breeding success ever recorded.
Magellanic penguins have averaged 0.71 chicks per breeding pair
since recording began in 1989/90 (n = 13, S.D.= 0.25). Prior to
1992/93 the average was 0.43 chicks per breeding pair, but between
1993/94 and 1999/2000 the average increased to 0.92 chicks per breeding
pair. A Mann-Whitney U test showed this difference to be significant
at the 5% level. Despite this improvement in breeding success, Magellanic
penguins have continued to decline in the Falkland Islands, and
over the last two seasons breeding success has averaged just 0.53
chicks per breeding pair, the lowest level since 1992/93.
Magdalena Island and Seno Otway are the closest major Magellanic
penguin colonies to the Falkland Islands with comparable breeding
conditions (ie. nesting occurring in burrows as per the Falklands).
Monitoring began at these two sites in 1996/97 to provide comparison
with the Falklands. Magdalena Island and Seno Otway are situated
in areas where large scale commercial fishing does not occur. Commercial
fishing did occur around Magdalena Island until a few years ago,
since when fishing has been banned in order to protect penguin populations
(Radl & Culik 1998). These colonies have shown increases in Magellanic
penguin population since studies began in 1996/97, using identical
methodology to that which has shown a population decease in the
Breeding success for Magellanic penguins has averaged 0.71 chicks
per breeding pair in the Falklands (n = 13, S.D.= 0.25), whilst
the two Chilean sites have averaged 1.40 chicks per breeding pair
(n = 10, S.D.= 0.08). A Mann-Whitney U test showed these differences
to be significant at the 5% level, with the lowest value for Chile
being higher than the highest value for the Falklands.
Comparison shows that lower breeding success in the Falklands
results from a two fold increase in nest abandonment during the
incubation phase, and a two and a half fold increase in chick mortality
after successful hatching. This increase in chick mortality in the
Falklands was due to increased levels of starvation and malnutrition.
Chick mortality during hatching showed no difference between Chile
and the Falklands.
Fledgling weights averaged 3.3kg in Chile, but only 2.7kg in the
Falklands, differing significantly at the 5% level using a Mann
Whitney U test. Chicks in the Falklands fledge around 10 days later
than in Chile. Mean foraging duration during chick rearing averaged
33.9 hours in the Falklands, and 13.5 hours in Chile, differing
significantly at the 5% level using a Mann Whitney U test.
Since recording began in 1993/94, Rockhopper breeding success
has remained within the range of 0.63 to 0.80 chicks per breeding
pair, with an overall average of 0.73 chicks per breeding pair (n
= 9, S.D.= 0.05). A lack of data makes it impossible to determine
whether Rockhopper breeding success was lower prior to 1993, during
their rapid population decline. However prior to 1995 virtually
no juveniles were returning to undertake their annual moult, suggesting
low overall recruitment.
In addition to the three main penguin species, the Falkland Islands
have small numbers of King and Macaroni penguin. The 1995/96 penguin
census recorded 339 King penguin chicks, which allowing for losses
during incubation and chick-rearing, and the staggered breeding
cycle, gives an estimated Falklands population of around 400 breeding
pairs. This is a tiny proportion of the estimated 1,500,000 breeding
pairs world-wide (Woehler 1993). The 2000/01 census recorded 275
chicks (Clausen 2001), a reduction of 19% since 1995/96.
There are no Macaroni penguin colonies in the Falklands, but a
few Macaroni penguins breed in Rockhopper colonies around the islands.
The total population of Macaroni penguins is estimated to be no
more than 50 breeding pairs (Bingham & Mejias 1999). Two very small
breeding colonies of Gentoo penguins were found in South America,
on Staten Island (about 30 breeding pairs) and on Hammer Island,
near Ushauia (about 5 breeding pairs). These are the first breeding
Gentoos recorded for South America, but other small colonies probably
Studies of breeding success in the Falklands showed no harmful
effects from tourism or the removal of Gentoo eggs for human consumption.
(NOTE: only Gentoo eggs can be legally taken in the Falklands, as
they are the only Falklands penguin that can re-lay after loosing
the first clutch of eggs.)
Diet sample analysis shows that Gentoo, Rockhopper and Magellanic
penguins all rely on species of fish and squid that are currently
taken commercially by the Falkland Islands' fishing industry, especially
loligo squid (Loligo gahi, d’Orbigny 1835) and blue whiting (Micromesistius
australis, Norman 1937) (Falkland Islands Government 1989, 2001).
These species make up a small proportion of the diet of Gentoos
(5.9% of observed diet) and Rockhoppers (10.2% of observed diet),
but 26.5% of the observed diet of Magellanic penguins. Magellanic
penguins continue to decline, while Gentoo and Rockhopper penguins
appear to have stopped declining.
For all three penguin species, the observed level of competition
with commercial fisheries will be an under-estimate. If there were
no commercial fishing activity the abundance of loligo squid and
blue whiting would be considerably higher. Since penguin diet in
the Falklands has only ever been studied under conditions of reduced
abundance of commercially harvested species due to commercial fishing,
the importance of such species to penguins under natural conditions
will be greatly under-estimated.
Further analysis shows that as the decline of Gentoo and Rockhopper
penguins bottomed out in the mid 1990s, a gradual change of diet
occurred, with less loligo squid being taken. Magellanic penguins
have also shown a change in diet away from loligo squid, but Magellanic
penguin populations have continued to decline despite this change.
The Falkland Islands is an important breeding site for Gentoo,
Southern Rockhopper and Magellanic penguins, but over the last 20
years all three have undergone population declines in the Falklands.
Despite a recent recovery in the Gentoo penguin population, total
penguin populations in the Falklands now total just 16% of that
estimated 20 years ago. This decline coincides with the development
of a large scale commercial fishing industry around the Falkland
Islands over the same time scale.
Southern Rockhopper and Magellanic penguins are only found in
the Falkland Islands and southern South America, but population
declines appear to have occurred only in the Falkland Islands. Census
and monitoring work in Chile indicates that Southern Rockhopper
and Magellanic penguin populations in Chile are stable, despite
their close proximity to the Falklands.
Rockhopper penguins do not change the location of their breeding
sites, so prolonged occupation kills off grasses and other vegetation,
leaving bare ground and lichen covered rock. In the Falkland Islands
most Rockhopper colonies are now found amidst much larger areas
of bare ground, where vegetation has been destroyed by colonies
that were once much larger. They appear rather like ponds that have
dried out to leave a small puddle at the centre. These visual signs
of large-scale decline are supported by census data, which shows
the current Rockhopper population in the Falklands to be just 11%
of that recorded 20 years ago.
By contrast most colonies in South America occupy the entire area
laid bare, and new nesting areas can be found where vegetation has
not yet been destroyed. On Staten Island (Isla de los Estados) colonies
have expanded at such a rate that large numbers of Rockhoppers are
nesting in dense grass which has not yet been killed off by nesting
activity. These visual signs suggest that the South American population
has remained stable, or in the case of Staten Island, undergone
a rapid increase. It is possible that some emigration has occurred
from the Falkland Islands to sites on coastal South America, such
as Staten Island.
There is no data on Rockhopper breeding success prior to 1993,
since when populations in the Falklands appear to have stopped declining,
and reached equilibrium. There is however strong observational evidence
that recruitment was very low in the Falklands prior to 1995. For
both Rockhopper and Magellanic penguins, juveniles and non-breeders
return to moult at their breeding site during January and February,
a time when colonies are being monitored to conduct chick counts.
Virtually no Rockhopper or Magellanic penguin juveniles were observed
around the breeding colonies during studies prior to 1995, suggesting
very low juvenile survival, despite the fact that colonies had been
observed producing fledglings during previous seasons. Since 1995
an increase in juveniles has been observed for Rockhopper penguins,
but not for Magellanic penguins. Colonies monitored in Chile have
shown healthy numbers of juveniles each year.
Breeding success for Magellanic penguins has been recorded annually
since 1989 in the Falkland Islands where large-scale commercial
fishing occurs, and since 1996 for two sites in southern Chile,
where large-scale commercial fishing is prohibited in order to protect
penguins. Breeding success in the Falkland Islands has averaged
0.71 chicks per breeding pair, whilst the average for the two Chilean
colonies has been 1.40 chicks per breeding pair. Large variations
in breeding success are usually associated with changes in food
availability (Boersma et al. 1990), and for the Falklands the main
factor influencing breeding success and recruitment is assumed to
be local food supply (Putz et al. 2001).
Low breeding success in the Falklands results from greater nest
abandonment during egg incubation, and higher chick mortality resulting
from starvation and malnutrition. Surviving chicks in the Falkland
Islands are of poor body condition and low weight at the time of
fledging (average 2.7kg) compared to Chile (average 3.3kg). This
suggests that no only do fewer chicks fledge in the Falklands, but
that fledglings also have a lower chance of surviving their first
year by virtue of being less well nourished. Comparison of juvenile
numbers returning to their natal colony to moult support this theory.
On Magdalena Island over four thousand juveniles are counted on
the beach each year, whilst in the Falkland Islands very few juveniles
are ever seen.
Gentoo, Rockhopper and Magellanic penguins all compete directly
for loligo squid (Loligo gahi) with the Falkland Islands fishing
industry (Putz et al. 2001). These penguins also take blue whiting
(Micromesistius australis) which is the main fish species targeted
by the Falkland Islands fishing industry. Dietary overlap for commercially
taken species is greatest for Magellanic penguins which are still
declining rapidly, less for Rockhopper penguins which have levelled
off at around 11% of their pre commercial fishing population, and
lowest for Gentoo penguins which have recovered following an initial
Over the last 10 years, the Falklands have experienced dietary
changes in all three penguins away from Loligo gahi. Putz (2001)
suggests that these dietary changes have been forced by reduced
abundance of Loligo gahi. These changes may be harmful in terms
of chick survival, since lobster krill, (Munida gregaria, Fabricius
1793), which now makes up one fifth of Magellanic penguin diet in
the Falklands, is not easily digested by Magellanic penguin chicks
(Thompson 1993). The theory that Magellanic penguins prefer not
to take Munida gregaria if more suitable prey are available, is
supported by diet sample studies in Chile. Magellanic penguins at
the two Chilean study sites show a complete lack of Munida gregaria
in their diet, even though Munida gregaria are present in great
abundance, forming a major part of the diet of King Cormorants nesting
on nearby Marta Island (Radl & Culik 1998).
Not only does the removal of preferred prey force penguins to
feed their chicks less favourable species, but it can also lead
to greater foraging duration, with chicks receiving less food (Radl
& Culik 1998). This increase in foraging duration is evident around
At the two Chilean study sites, where large-scale commercial fishing
is no longer permitted, Magellanic penguins average 13.5 hours to
return with food for their chicks (Radl & Culik 1998). In the Falkland
Islands, foraging trip duration averages 33.9 hours. This huge increase
in foraging duration coincides with a 50% reduction in breeding
success, higher chick starvation, lower fledging weight, and a substantial
reduction in juvenile survival, compared to populations in Chile.
Reproductive success depends on food availability (Crawford &
Dyer 1995), and competition for food with commercial fisheries is
a recognised cause of population decline in other regions (Brown
& Nettleship 1984, Culik & Luna Jorquera 1997, Duffy et al. 1987).
Breeding success and fledging weights are recognised bioindicators
for monitoring the marine environment and marine food supplies (Cairns
1987, Furness & Camphuysen 1997), and Magellanic penguins suggest
that the marine environment around the Falkland Islands may be in
Prior to 1988 fishing around the Falkland Islands was intensive
and totally unregulated, threatening fish and squid stocks (Patterson
1987). No catch data or diet sample data exists for this period,
during which huge penguin population declines occurred. Following
a mass starvation of penguins in 1986, when many Rockhopper colonies
lost over half their adult population (Keymer et al. 2001), it was
agreed that commercial fishing around the Falklands needed to be
regulated. This regulation was introduced in 1988, since when catch
rates have gradually been reduced by controlling the number of boats
licensed to fish (Falkland Islands Government 1989, 2001).
For squid, the catch rate per unit effort of fishing vessels is
now monitored on a daily basis to determine when the target of 60%
biomass has been removed each year. The remaining 40% biomass is
deemed by the Falkland Islands Government to be adequate as prey
for seabirds and marine mammals, and as breeding stock for the following
season. Whilst this may ensure sustainable use of stocks as a financial
resource, it seems unreasonable to suppose that 60% of the biomass
can be removed prior to the breeding season of seabirds and marine
mammals, without having an impact on those species which rely on
such prey for successful breeding.
Diet sample analysis shows that there is competition between penguins
and commercial fisheries for loligo squid (Loligo gahi) (Putz et
al. 2001) and potential competition for blue whiting (Micromesistius
australis). Since diet samples have only ever been taken in the
presence of commercial fishing activities, the proportion of commercially
harvested species found in penguin diet will be greatly reduced.
Diet analysis will therefore greatly under-estimate the level of
competition between penguins and commercial fisheries.
Any competition for food is likely to be exacerbated by the fact
that the commercial fishing season runs until the end of October,
when penguins and other seabirds begin breeding. Since stocks are
managed by recording the daily decline of catch per unit effort,
it stands to reason that penguins will also encounter this decline
in catch per unit effort as they enter their breeding phase.
Breeding places great demands on adult penguins to find sufficient
food for themselves and their chicks. Each adult must first catch
sufficient food for its own needs, and a surplus for its chicks,
at a time when its foraging range is greatly reduced by the need
to return to the nest. A reduction in food abundance can therefore
lead to greater foraging duration, less food being brought back
to chicks, and reduced chick survival.
It is probable that the rapid penguin declines observed in the
Falklands during the 1980s were a result of uncontrolled commercial
fishing. Elephant Seals and Southern Sealions, which also feed on
species taken by the commercial fishing industry, also underwent
huge population declines in the Falklands during the same period
(Galimberti 2000, Strange 1992, Thompson & Duck 1996). As is the
case for penguins, these species also occur in South America where
no such declines occurred. King Penguins and Fur Seals which feed
on prey not commercially harvested, increased in population around
the Falklands over the same period.
During the late 1970s and early 1980s, fish and squid stocks were
heavily fished without any monitoring or control. In 1986 a lack
of food led to mass starvation of adult penguins, and public concern
called for controls over commercial fishing. Following the establishment
of a regulatory body in 1988, the effects of over-fishing have been
greatly mitigated through reduction of fishing effort and control
of species taken.
Chick and juvenile survival have shown some signs of improvement,
and Gentoo and Rockhopper populations have stopped declining. These
populations appear to have reached equilibrium with the current
fishing regime, albeit at a much lower level than prior to the 1980s.
Magellanic penguins have continued to decline however, and it is
likely that their greater dependence on species which are still
commercially harvested is a major factor.
Concerns about the removal of Gentoo penguin eggs for human consumption
were not borne out by the data, which suggest little effect on breeding
success. Unlike most other penguins, Gentoos have the ability to
relay within a few days of loosing their clutch. This enables them
to rear chicks successfully after losing their first brood. Although
egging could hardly be advocated by any conservationist, in the
Falklands it is a tradition which is gradually dying out, due to
an improved infra-structure that allows people in remote areas to
purchase a wider range of food items. Conservationists have taken
the view that it is preferable to let the tradition die a natural
death, rather than risk a resurgence by threatening people's right
to continue the practice.
Tourism is another potential cause for concern. The Falkland Islands
are now one of the world's most popular destinations for penguin
spotters, and this growing tourist industry is a potential threat
to Falklands penguins. The Falkland Islands received around 35,000
visitors during the 2001/2002 season (Fowler 2002).
Over recent years a number of scientific reports have demonstrated
that even well-behaved visitors can cause stress and increased heart-rate
in penguins and seabirds, but these factors are not necessarily
harmful to the bird or its fecundity. Seabirds are subjected to
varying levels of stress in their natural environment, so it was
important to monitor the effects of tourism in its wider perspective,
by conducting long-term studies of population trends and breeding
success. Breeding success in particular provides a useful measure
of visitor disturbance. Careless visitors have the potential to
disturb breeding penguins in a number of ways:
- Incubating birds may be frightened away allowing predators to
take eggs or young.
- Raised metabolic rates brought on by stress may lead to greater
- Natural behaviour, such as courtship or the feeding of young,
may be disrupted.
- Adults could be scared away completely, causing them to abandon
eggs or young.
- Severe disturbance could lead to adults or young being killed
- Birds which live in burrows may be killed if the burrow collapses
under human weight.
These potential consequences of disturbance should all lead to
reduced breeding success if they are occurring at a significant
level, however studies of penguin breeding success in the Falklands
and southern Chile show no harmful effects from tourism so far.
Other penguin studies have reached similar conclusions (Cobley &
Ecotourism undoubtedly has a number of benefits. It provides wildlife
with a commercial value, giving support for its protection within
the commercial sector. It also educates and entertains the people
who see the wildlife, raising awareness and gathering support for
wildlife protection within the community as a whole. It is difficult
to provide strong argument for wildlife protection unless people
can relate to wildlife on a personal level. It is therefore important
to promote ecotourism, whilst at the same time ensuring that such
tourism does not damage the wildlife resources which people come
There are clearly a number of threats facing penguin populations
in the Falkland Islands, but penguin populations appear very robust
to disturbance and moderate levels of exploitation on land. Major
changes to the landscape brought about by livestock, the removal
of eggs for food, and exploitation as a resource for tourism, all
appear to have had low impact on penguin populations in the Falklands.
Marine pollution around the Falklands has so far been limited to
a spate of oil spills that occurred during drilling operations in
1998, and high levels of cadmium common to the Antarctic region
in general, that may be due to natural factors (Keymer et al. 2001).
The only major predators of penguins, Southern Sealions, have suffered
a 97% decline in the Falklands (Thompson & Duck 1996) making them
an unlikely cause of penguin decline.
Even in a healthy population, starvation is the main cause of
chick mortality for Magellanic penguins (Scolaro 1990, Boersma 1991),
and in the Falkland Islands low breeding success, high chick mortality,
low fledging weight and low recruitment are largely due to low food
supply (Putz et al. 2001). On at least one occasion this low food
supply has also led to mass starvation of adult penguins (Keymer
et al. 2001).
Whilst it is unrealistic to expect the Falkland Islands Government
to halt commercial fishing activity, which is a major source of
revenue to the islands, minor changes could be adopted which would
mitigate the effects of commercial fishing on penguin populations,
without greatly effecting revenue. At present commercial fishing
vessels are permitted to fish within 3 miles (5km) of the coastline,
even where penguin breeding sites are located. It was proposed at
the Spheniscus Penguin Conservation Workshop (September 2000, Chile)
that fishing vessels in the Falkland Islands should be excluded
from within 30 miles (48km) of penguin breeding sites during the
breeding season. Such measures would protect feeding areas within
the penguins' daily foraging range, whilst reducing the total area
available to fishing vessels by just 4%.
Satellite tracking has shown that around the Falkland Islands,
Magellanic penguins have a mean foraging range of about 16km during
incubation, and 7km during chick rearing, with a maximum distance
of 39km being recorded during chick rearing. Gentoo penguins have
a mean foraging range of 6km, with a maximum of less than 25km being
recorded (Boersma et al. 2001). These foraging distances lie well
within the 30 mile (48km) exclusion zone requested at the Spheniscus
Penguin Conservation Workshop. Rockhopper penguins were recorded
foraging outside the requested exclusion zone, with short foraging
trips averaging less than 6km, being supplemented by long distance
foraging trips of well over 100km. Even so Rockhoppers made more
use of inshore waters during the critical chick-rearing stage (Boersma
et al. 2001).
Magellanic penguins fitted with time-depth recorders at the two
Chilean study sites showed similar results, with foraging beginning
at around 7km from the breeding site. Mean foraging range was 25km,
and maximum foraging ranges for the two sites were 33km (Seno Otway)
and 47km (Magdalena Island) (Radl & Culik 1998).
Inshore fishing around the Falklands has a negative impact on
Gentoo, Rockhopper and Magellanic penguins (Boersma et al. 2001).
It is therefore probable that if a fishing exclusion zone were established
around penguin breeding sites in the Falkland Islands, as has been
done around Magdalena Island in Chile, that this would allow an
increase in food availability within the penguins' foraging range.
This in turn should lead to a decrease in foraging duration, an
increase in food brought back to chicks, and an increase in chick
survival and fledging weights, as has been observed since the exclusion
of large-scale commercial fishing from around Magdalena Island.
The exclusion of fishing would only be required just prior to and
during the breeding season, and it might also help protect Falklands
penguins from their other major threat, marine pollution.
During 1998 an oil rig was sent to the Falkland Islands to look
for oil. During the five months of operation 3 separate oil spills
occurred killing hundreds of penguins. It is unlikely that the oil
came from the rig itself, which claimed never to have found oil
in commercially viable quantities. The oil is presumed to have come
from oil rig supply vessels operating in Falkland waters at the
time. No further oil spills have occurred since the oil rig and
its supply vessels left the Falklands.
In 1995 the United Kingdom, Argentina and the Falkland Islands
set aside a Special Area of Co-operation for future oil exploration
and development, so there is little doubt that oil exploration around
the Falklands will recommence in the near future. Unless environmental
protection is greatly improved, it is probable that many more penguins
will die in unnecessary oil spills, as happens each year along coastal
The Falkland Islands are an internationally important breeding
site for penguins, and it is vital that the Falkland Islands Government
accept their responsibility to protect this natural resource. Rockhopper
penguins now number just 11% of the population recorded in the Falklands
18 years ago, and they are now classified as Vulnerable under IUCN
guidelines. Magellanic penguins have undergone a similar magnitude
of decline, and are still declining. Sealions and Elephant seals
have also undergone major declines since the establishment of a
commercial fishing industry in the Falklands.
It is very difficult to prove the link between the decline of
these species, and the establishment of large-scale commercial fishing
around the Falklands, just as it is difficult to prove links between
smoking and individual cases of heart disease or lung cancer. However,
many take the view that for non-target species, and especially protected
species such as penguins, that the burden of proof for no harm lies
with the exploiter (Boersma et al. 2001).
On a per capita basis, the Falklands is one of the wealthiest
places on earth, with an annual government income of over US$30,000
for every person living in the islands. As such there is no reason
why financial interests should outweigh the need for adequate protection
of Falklands wildlife. If a relatively poor country such as Chile
can protect the waters around important penguin breeding sites such
as Magdalena Island, then there is no reason why the Falkland Islands
cannot offer similar concessions in the name of wildlife conservation.
In 2002, the IUCN published its Spheniscus Penguin Conservation
Workshop Report (Luna et al. 2002). This report summarises the recommendations
of 43 of the world's leading penguin researchers and conservationists,
brought together in September 2000 for the 4th International Penguin
Conference and Spheniscus Penguin Conservation Workshop, to discuss
penguin conservation measures. The report states:
"Recommend that there be no inshore fisheries (within 30 miles
of the coast) in the Falklands. Restrict industrial fishing from
areas of known concentrated penguin use at sea (including wintering
and foraging areas for fledglings). Argentina and the Falklands
should establish an integrated series of marine reserves and zones,
subject to adaptive management based on continuing research and
monitoring, to benefit all species (fish, seabirds, marine mammals)."
The Environmental Research Unit has requested the Falkland Islands
Government to adopt the measures recommended in the report, but
they have refused.
Thanks go to the Environmental Research Unit, Falklands Conservation,
Falkland Islands Fisheries Department, Corporación Nacional Forestal
(Chile), Fundación Otway (Chile), Aerovias DAP, Arne Radl, the rangers
of Magdalena Island, and the crews of "Melinka", "Tierra Australis",
"Hundy" and "Don Jorge" for logistical support, and to research
assistants Nidia Mendez and Cici Legoe. Thanks also to the Conservation
& Research Foundation (Connecticut, USA), the PADI Foundation (Beverly
Hills, USA), Fauna and Flora International (UK), and the Darwin
Initiative (British Government) for providing funding.
Bennett AG (1933) The penguin population of the Falkland Islands
in 1932/33. Government Press, Falkland Islands. 4pp.
Bingham M & Mejias E (1999) Penguins of the Magellan Region. Scientia
Marina 63, Supl. 1. Pp 485-493.
Boersma PD, Stokes DL & Yorio PM (1990) Reproductive variability
and historical change of Magellanic penguins at Punta Tombo, Argentina.
In: Davis LS & Darby JT (eds) Penguin Biology. Academic Press, San
Diego, pp 15-43.
Boersma PD (1991) Asynchronous hatching and food allocation in
the Magellanic penguin. Acta XX Congressus Internationalis Ornithologici:
Boersma PD, Stokes DL & Strange IJ (2001) Tracking breeding penguins
at New Island South Reserve: An overview of work carried out between
1997 and 2001. New Island South Conservation Trust Supplement 2,
Stanley, Falkland Islands, 4pp.
Brown RG & Nettleship DN (1984) Capelin and seabirds in the Northwest
Atlantic. In Nettleship DN, Sanger GA, Springer PF (eds) Marine
birds: their feeding ecology and commercial fisheries relationships.
Canadian Wildlife Services Publication, Ottawa, Canada. pp 184-195.
Cairns DK (1987) Seabirds as indicators of marine food supplies.
Biological Oceanography 5: 261-271
Clausen A (2000) Falkland Islands Seabird Monitoring Programme
Report. Falklands Conservation Report SMP8, Stanley, Falkland Islands.
Clausen A (2001) Falkland Islands Penguin Census 2000/01. Falklands
Conservation Report, Stanley, Falkland Islands. 27pp.
Cobley ND & Shears JR (1999) Breeding performance of gentoo penguins
at a colony exposed to high levels of human disturbance. Polar Biology
Crawford RJM & Dyer BM (1995) Responses by four seabird species
to a fluctuating availability of Cape Anchovy Engraulis capensis
off South Africa. Ibis 137:329-339.
Croxall JP, McInnes SJ & Prince PA (1984) The status and conservation
of seabirds at the Falkland Islands. In Status and conservation
of the world's seabirds. ICBP Technical Publication No.2, (ed. JP
Croxall, PGH Evans & RW Schreiber), 271-291, ICBP, Cambridge.
Culik BM & Luna Jorquera G (1997) Satellite tracking of Humboldt
penguins (Spheniscus humboldti) in northern Chile. Marine Biology
Duffy DC, Wilson RP, Ricklefs RE, Broni SC & Veldhuis H (1987)
Penguins and purse seiners: competition or coexistence? Natl Geogr
Res 3: 480-488.
Falkland Islands Government (1989) Falkland Islands Interim Conservation
and Management Zone Fisheries Report '87/88. Falkland Islands Government
Falkland Islands Government (2001) Fisheries Department Fisheries
Statistics, Volume 5, 2000. FIG Fisheries Department, Stanley. 68pp.
Fowler JAT (2002) Review of trends and changes in Falklands Tourism
1995 - 2001. Falkland Islands Tourist Board, Stanley, Falkland Islands.
Frere E, Gandini M, Gandini P, Holik T, Lichtschein V & Day MO
(1993) Variación anual en el número de adultos reproductivos en
una nueva colonia de pingüino penacho amarillo en Isla Pingüino
(Santa Cruz, Argentina). Hornero 13: 293-294.
Furness RW & Camphuysen CJ (1997) Seabirds as monitors of the
marine environment. ICES Journal of Marine Science 54: 726-737.
Galimberti F (2000) Elephant Seals of the Falklands. Elephant
Seal Research Group report, Milano, Italy. 31pp.
Keymer IF, Malcolm HM, Hunt A & Horsley DT (2001) Health evaluation
of penguins following mortality in the Falklands. Diseases of Aquatic
Organisms 45(3): 159-169.
Lewis Smith RI & Tallowin JRB (1979) The distribution and size
of king penguin rookeries on South Georgia. British Antarctic Survey
Bulletin 49: 259-276.
Luna G, Hennicke J, Wallace R, Simeone A, Wolfaardt A, Whittington
P, Ellis S and McGovern M (2002) Spheniscus Penguin Conservation
Workshop Final Report, IUCN/SSC Conservation Breeding Specialist
Group, Apple Valley, USA. 83pp.
Patterson KR (1987) Fishy events in the Falkland Islands. New
Scientist 1562: 44-48.
Putz K, Ingham RJ, Smith JG & Croxhall JP (2001) Population trends,
breeding success and diet composition of gentoo, magellanic and
rockhopper penguins in the Falkland Islands. Polar Biology 24: 793-807.
Radl A & Culik BM (1998) Foraging behaviour and reproductive success
in Magellanic penguins: a comparative study of two colonies in southern
Chile. Marine Biology 133: 381-393.
Scolaro JA (1990) Effects of nest density on breeding success
in a colony of Magellanic penguins (Spheniscus magellanicus). Colonial
Waterbirds 13(1): 41-49.
Strange IJ (1992) Wildlife of the Falkland Islands and South Georgia.
Harper Collins, London. 188pp.
Thompson D & Duck CD (1996) Southern Sea Lions in the Falkland
Islands. Sea Mammal Research Unit Report, Cambridge. 48pp.
Thompson KR (1993) Variation in Magellanic penguin diet in the
Falkland Islands. Marine Ornithology 21: 57-67.
Venegas C (1984) Estado de las poblaciones de Pingüino de Penacho
Amarillo y Macaroni en la Isla Noir, Chile. Informe Instituto de
la Patagonia 33, Punta Arenas, Chile. 25pp.
Venegas C (1991) Estudio de cuantificacion poblacional de pingüinos
crestados en Isla Recalada. Informe Instituto de la Patagonia 55,
Punta Arenas, Chile. 27pp.
Wilson RP (1984) An improved stomach pump for penguins and other
seabirds. Journal of Field Ornithology 55: 9-12.
Woehler EJ (1993) The distribution and abundance of Antarctic
and Subantarctic Penguins. SCAR, Cambridge. 76pp.
Bingham, M. (2002) The decline of Falkland Islands penguins
in the presence of a commercial fishing industry.
Bingham, M. (1998) The distribution, abundance and population
trends of Gentoo, Rockhopper and King penguins at the Falkland
Islands. Orxy 32(3): 223-32.
Bingham, M. (1996) Censo de los pingüinos de las Islas Falklands.
Unpublished Spanish resume of above.
Bingham, M. (1998) Penguins of South America and the Falkland
Islands. Penguin Conservation 11(1): 8-15.
Bingham M. and Mejias E. (1999) Penguins of the Magellan Region.
Scientia Marina Vol:63, Supl. 1: 485-493
Bingham, M. (1999) Field Guide to Birds of the Falkland Islands
7. Bingham, M and Herrmann, T (2008) Magellanic Penguin Monitoring Results for Magdalena Island 2000-08. Anales Instituto Patagonia (Chile) 36(2): 19-32.