Winter Migration of Magellanic Penguins From the Southernmost Distributional Range Mollie Ryan...
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Winter Migration of Winter Migration of Magellanic Magellanic
Penguins From the Penguins From the Southernmost Southernmost Distributional Distributional
RangeRange
Mollie RyanMollie Ryan
BI257: Winter BI257: Winter EcologyEcology
General Info: The SubjectsGeneral Info: The Subjects
22 magellanic 22 magellanic penguins penguins ((Spheniscus Spheniscus magellanicusmagellanicus) ) from Isla Martillo from Isla Martillo in the Beagle in the Beagle Channel, Channel, ArgentinaArgentina
General Info: The StudyGeneral Info: The Study
Winter migration after molt Winter migration after molt Satellite tracked a total of 22 Satellite tracked a total of 22
penguins for three yearspenguins for three years In 2004, seven penguinsIn 2004, seven penguins In 2005, seven penguins In 2005, seven penguins In 2006, eight penguinsIn 2006, eight penguins
General Info: Top PredatorGeneral Info: Top Predator
One of the top One of the top predators in the predators in the Patagonian Shelf (the Patagonian Shelf (the southernmost part of southernmost part of Argentina)Argentina)
Breeding distribution is Breeding distribution is restricted to coastal restricted to coastal locations between locations between Cape Horn (southern Cape Horn (southern tip of Chile) and 42tip of Chile) and 42°°S S (about halfway point of (about halfway point of Argentina) and sites on Argentina) and sites on Falkland IslandsFalkland Islands
General Info: PopulationGeneral Info: Population
Total world population ~ 1 million Total world population ~ 1 million breeding pairsbreeding pairs
An additional 100,000 breeding An additional 100,000 breeding pairs on Falkland Islandspairs on Falkland Islands
Numbers have decreased at many Numbers have decreased at many breeding sites over the last part of breeding sites over the last part of the twentieth centurythe twentieth century
General Info: Population General Info: Population (cont’d)(cont’d)
Largest colony is found on Punta Largest colony is found on Punta Tombo, ArgentinaTombo, Argentina
An important breeding colony is Isla An important breeding colony is Isla Martillo in the Beagle Channel, Martillo in the Beagle Channel, ArgentinaArgentina
It is located at the boundary between It is located at the boundary between the Atlantic and Pacific oceansthe Atlantic and Pacific oceans One of the southernmost coloniesOne of the southernmost colonies
General Info: Population General Info: Population (cont’d)(cont’d)
Annual variability in breeding Annual variability in breeding success related to changes in quality success related to changes in quality and quantity of diet and/or to and quantity of diet and/or to weather conditionsweather conditions
Populations impacted by human-Populations impacted by human-related factors:related factors: Commercial fishingCommercial fishing Oil pollutionOil pollution Disturbance due to tourismDisturbance due to tourism
Purpose of Purpose of StudyStudy
Investigate winter migration patterns of these Investigate winter migration patterns of these penguins originating from the southern range penguins originating from the southern range of their breeding distributionof their breeding distribution
Identify distribution of penguinsIdentify distribution of penguins Identify potential conflicts with human Identify potential conflicts with human
activitiesactivities
Materials and MethodsMaterials and Methods
Fieldwork conducted at the magellanic Fieldwork conducted at the magellanic penguin breeding colony on Isla Martillo penguin breeding colony on Isla Martillo
Comprised of about 2,000 breeding pairsComprised of about 2,000 breeding pairs 22 adults (10 females, 12 males) were 22 adults (10 females, 12 males) were
randomly selected and attached with randomly selected and attached with satellite transmitterssatellite transmitters 23 March 2004 – 7 penguins23 March 2004 – 7 penguins 22 March 2005 – 7 penguins22 March 2005 – 7 penguins 17 March 2006 – 8 penguins17 March 2006 – 8 penguins
Materials and MethodsMaterials and Methods Transmitters attached on the mid-line Transmitters attached on the mid-line
of the back using black tape and of the back using black tape and synthetic rubber gluesynthetic rubber glue
To minimize hydrodynamic drag:To minimize hydrodynamic drag: In 2004, devices were attached as far In 2004, devices were attached as far
distally as possible without impairing distally as possible without impairing preen glandpreen gland
In 2005 and 2006, devices were attached In 2005 and 2006, devices were attached to the middle of the back to not to the middle of the back to not compromise the penguins’ balancecompromise the penguins’ balance
Devices were then covered with a layer of Devices were then covered with a layer of quick epoxyquick epoxy
Materials and MethodsMaterials and Methods
The KiwiSat 101 satellite transmitter The KiwiSat 101 satellite transmitter had maximum dimensions of 130 x had maximum dimensions of 130 x 35 x 20 mm35 x 20 mm hydrodynamically-shapedhydrodynamically-shaped
Powered by 2 AA lithium cellsPowered by 2 AA lithium cells Weighed about 100 gWeighed about 100 g
Equivalent to 2.7% of mean penguin Equivalent to 2.7% of mean penguin body mass of 3.7 body mass of 3.7 ±± 0.5 kg 0.5 kg
Materials and MethodsMaterials and Methods To reduce further hydrodynamic drag, To reduce further hydrodynamic drag,
a flexible antenna protruded at an a flexible antenna protruded at an angle of 60angle of 60°° from the rear of the from the rear of the devicedevice 170 mm long and 3 mm in diameter170 mm long and 3 mm in diameter
In 2006, along with five KiwiSat 101, In 2006, along with five KiwiSat 101, three KiwiSat 202 were usedthree KiwiSat 202 were used Each had maximum dimensions of 60 x 35 Each had maximum dimensions of 60 x 35
x 22 mmx 22 mm Weighed about 60gWeighed about 60g
Equivalent to about 2% of the mean penguin Equivalent to about 2% of the mean penguin body mass of 3.0 body mass of 3.0 ±± 0.4 kg 0.4 kg
Various KiwiSat 101 transmittersVarious KiwiSat 101 transmitters
KiwiSat 202 transmitter for a KiwiSat 202 transmitter for a penguin or small sea turtlepenguin or small sea turtle
Materials and MethodsMaterials and Methods
Devices were programmed to transmit on Devices were programmed to transmit on a cycle of 6 hr on / 18 hr off with a a cycle of 6 hr on / 18 hr off with a repetition period of 60 srepetition period of 60 s
Equipped with a saltwater switch that Equipped with a saltwater switch that prevented transmission while under water prevented transmission while under water to conserve battery lifeto conserve battery life
The KiwiSat 101 recorded and transmitted The KiwiSat 101 recorded and transmitted time penguins spent at the surfacetime penguins spent at the surface
Transmitter life: 84 days with 2 AA Transmitter life: 84 days with 2 AA batteriesbatteries
ResultsResults
A total of 1,340 daily A total of 1,340 daily positions were obtained positions were obtained from the 22 magellanic from the 22 magellanic penguinspenguins
The mean minimum The mean minimum distance traveled by all distance traveled by all penguins was 1,440 penguins was 1,440 ±± 685 685 kmkm
The mean distance The mean distance covered per day was 23.2 covered per day was 23.2 ±± 6.6 km 6.6 km
ResultsResults
Penguins spent 52.8 Penguins spent 52.8 ±± 6.3% of their 6.3% of their time at sea submergedtime at sea submerged
Sex-related differences were not Sex-related differences were not found with regard to transmission found with regard to transmission duration and migratory parametersduration and migratory parameters
ResultsResults All 22 penguins left Beagle Channel in an easterly All 22 penguins left Beagle Channel in an easterly
directiondirection Most (except for three) penguins traveled around Most (except for three) penguins traveled around
the southeasterly tip of South America into the the southeasterly tip of South America into the AtlanticAtlantic
They headed north and migrated along the They headed north and migrated along the Argentine coast until transmission ceasedArgentine coast until transmission ceased
Migratory behavior was decomposed into periods Migratory behavior was decomposed into periods of rapid movement in a northerly direction, of rapid movement in a northerly direction, interspersed with periods, during which the birds interspersed with periods, during which the birds remained for some time in a certain arearemained for some time in a certain area
Migration routes Migration routes in 2004in 2004
Fips = red (filled square)Fips = red (filled square) Flo = green (filled diamond)Flo = green (filled diamond) Fyjima = yellow (plus symbol)Fyjima = yellow (plus symbol) Lu = pink (filled circle)Lu = pink (filled circle) Miriam = blue (filled triangle)Miriam = blue (filled triangle) Silvester = brown (rectangle)Silvester = brown (rectangle) WaRu = black (filled inverted WaRu = black (filled inverted
triangle)triangle)
Migration routes in Migration routes in 20052005
Biggi = black (filled circle)Biggi = black (filled circle) Egregrius = red (rectangle)Egregrius = red (rectangle) Eva = brown (filled square)Eva = brown (filled square) Jennifer = pink (filled diamond)Jennifer = pink (filled diamond) Jupp = blue (filled triangle)Jupp = blue (filled triangle) Schroder = green (filled Schroder = green (filled
inverted triangle)inverted triangle) The Boss = yellow (plus symbol)The Boss = yellow (plus symbol)
Migration routes in Migration routes in 20062006
Florian = blue (filled circle)Florian = blue (filled circle) Gimmy = light blue (open Gimmy = light blue (open
rectangle)rectangle) Kira = brown (filled diamond)Kira = brown (filled diamond) Klaus = green (filled triangle)Klaus = green (filled triangle) NN1 = pink (filled inverted NN1 = pink (filled inverted
triangle)triangle) NN2 = black (open rectangle)NN2 = black (open rectangle) NN3 = red (plus symbol)NN3 = red (plus symbol) Whitney = yellow (filled Whitney = yellow (filled
square)square)
Discussion: Impact of Discussion: Impact of Transmitter?Transmitter?
The external attachment of devices is The external attachment of devices is likely to have an impact on behaviorlikely to have an impact on behavior
Likely an increase in hydrodynamic drag, Likely an increase in hydrodynamic drag, which negatively impacts on a great which negatively impacts on a great variety of foraging parametersvariety of foraging parameters
This effect is more pronounced in This effect is more pronounced in transmitters equipped with an antenna, transmitters equipped with an antenna, which increases hydrodynamic drag even which increases hydrodynamic drag even moremore
After 2005, the position of the transmitters After 2005, the position of the transmitters was moved further to the body centerwas moved further to the body center
Discussion: Impact of Discussion: Impact of Transmitter?Transmitter?
All devices ceased All devices ceased transmission during transmission during migrationmigration
A possible reason:A possible reason: Penguins detached Penguins detached
satellite transmitter satellite transmitter by biting and by biting and breaking the feathers breaking the feathers attached to itattached to it
Discussion: Migration Discussion: Migration PatternsPatterns
Penguins originating from the Falkland Penguins originating from the Falkland Islands (51°S) remained exclusively in the Islands (51°S) remained exclusively in the Atlantic Ocean, then migrated northwardsAtlantic Ocean, then migrated northwards
One penguin migrated into the Pacific, but One penguin migrated into the Pacific, but headed northwards as wellheaded northwards as well
A north-bound winter migration appears to A north-bound winter migration appears to be a general feature for magellanic be a general feature for magellanic penguinspenguins
Discussion: Migration Patterns Discussion: Migration Patterns (cont’d)(cont’d)
Due to the temporal Due to the temporal and spatial differences and spatial differences in their migration in their migration patterns, penguins patterns, penguins experience qualitative experience qualitative and quantitative and quantitative variations in food variations in food availabilityavailability
However, nothing is However, nothing is known of a magellanic known of a magellanic penguin diet during penguin diet during winter monthswinter months
Discussion: Migration Patterns Discussion: Migration Patterns (cont’d)(cont’d)
Northbound migration can be related Northbound migration can be related to decreasing sea temperatures, light to decreasing sea temperatures, light levels and progressively impeding levels and progressively impeding planktonic growth in more southerly planktonic growth in more southerly regions as season progressedregions as season progressed
Migration is driven by formation and Migration is driven by formation and subsequent dissipation of areas with subsequent dissipation of areas with enhanced food availabilityenhanced food availability
Discussion: Human Activity Discussion: Human Activity InteractionsInteractions
Magellanic penguins are increasingly Magellanic penguins are increasingly exposed to human-related activitiesexposed to human-related activities
Prey of the penguins is commercially Prey of the penguins is commercially exploited and population crashes may exploited and population crashes may happen due to the poorly-managed happen due to the poorly-managed fisheriesfisheries
There are mortalities associated with the There are mortalities associated with the fishing itselffishing itself
Example: in Puerto Quequen, Argentina, Example: in Puerto Quequen, Argentina, 100 magellanic penguins die each year as 100 magellanic penguins die each year as bycatch in coastal fishingbycatch in coastal fishing
Discussion: Human Activity Discussion: Human Activity Interactions (cont’d)Interactions (cont’d)
Oil pollution is a much more obvious effect on Oil pollution is a much more obvious effect on penguin survivalpenguin survival
In 1991, about 15,000 magellanic penguins died In 1991, about 15,000 magellanic penguins died as a consequence of one single oil incidentas a consequence of one single oil incident
Each year, more than 40,000 penguins die each Each year, more than 40,000 penguins die each along the Argentine coast of Chubut due to along the Argentine coast of Chubut due to chronic oil pollutionchronic oil pollution
Magellanic penguin breeding population located Magellanic penguin breeding population located in the northern distributional range has in the northern distributional range has decreased a lot over the past decade which decreased a lot over the past decade which greatly indicates harmful interaction with human greatly indicates harmful interaction with human activitiesactivities
ConclusionsConclusions
Winter migration after molt was satellite Winter migration after molt was satellite tracked for three yearstracked for three years
Potential impact of transmitters on behaviorPotential impact of transmitters on behavior Northward migration during winter is Northward migration during winter is
related to decreasing sea temperatures, related to decreasing sea temperatures, light levels, and food availabilitylight levels, and food availability
Harmful human activity interactions include Harmful human activity interactions include poorly-managed fisheries, fishing gear, and poorly-managed fisheries, fishing gear, and oil pollutionoil pollution These decrease breeding populations in the These decrease breeding populations in the
northern distributional rangenorthern distributional range
Thank you!Thank you!Questions?Questions?
Putz, K., Schiavini, A., Rey, A.R., and B. Luthi. 2007. Winter migration of magellanic penguins (Spheniscus magellanicus) from the southernmost distributional range. Mar Biol 152: 1227-1235.