Winter Migration of Magellanic Penguins From the Southernmost

Winter Migration of Magellanic Penguins From the Southernmost Distributional Range Mollie Ryan BI 257: Winter Ecology

General Info: The Subjects n 22 magellanic penguins (Spheniscus magellanicus) from Isla Martillo in the Beagle Channel, Argentina

General Info: The Study n n Winter migration after molt Satellite tracked a total of 22 penguins for three years In 2004, seven penguins n In 2005, seven penguins n In 2006, eight penguins n

General Info: Top Predator n n One of the top predators in the Patagonian Shelf (the southernmost part of Argentina) Breeding distribution is restricted to coastal locations between Cape Horn (southern tip of Chile) and 42°S (about halfway point of Argentina) and sites on Falkland Islands

General Info: Population n Total world population ~ 1 million breeding pairs An additional 100, 000 breeding pairs on Falkland Islands Numbers have decreased at many breeding sites over the last part of the twentieth century

General Info: Population (cont’d) n n n Largest colony is found on Punta Tombo, Argentina An important breeding colony is Isla Martillo in the Beagle Channel, Argentina It is located at the boundary between the Atlantic and Pacific oceans n One of the southernmost colonies

General Info: Population (cont’d) n n Annual variability in breeding success related to changes in quality and quantity of diet and/or to weather conditions Populations impacted by human-related factors: Commercial fishing n Oil pollution n Disturbance due to tourism n

Purpose of Study n n n Investigate winter migration patterns of these penguins originating from the southern range of their breeding distribution Identify distribution of penguins Identify potential conflicts with human activities

Materials and Methods n n n Fieldwork conducted at the magellanic penguin breeding colony on Isla Martillo Comprised of about 2, 000 breeding pairs 22 adults (10 females, 12 males) were randomly selected and attached with satellite transmitters n n n 23 March 2004 – 7 penguins 22 March 2005 – 7 penguins 17 March 2006 – 8 penguins

Materials and Methods n n Transmitters attached on the mid-line of the back using black tape and synthetic rubber glue To minimize hydrodynamic drag: In 2004, devices were attached as far distally as possible without impairing preen gland n In 2005 and 2006, devices were attached to the middle of the back to not compromise the penguins’ balance n Devices were then covered with a layer of quick epoxy n

Materials and Methods n The Kiwi. Sat 101 satellite transmitter had maximum dimensions of 130 x 35 x 20 mm n n n hydrodynamically-shaped Powered by 2 AA lithium cells Weighed about 100 g n Equivalent to 2. 7% of mean penguin body mass of 3. 7 ± 0. 5 kg

Materials and Methods n To reduce further hydrodynamic drag, a flexible antenna protruded at an angle of 60° from the rear of the device n n 170 mm long and 3 mm in diameter In 2006, along with five Kiwi. Sat 101, three Kiwi. Sat 202 were used Each had maximum dimensions of 60 x 35 x 22 mm n Weighed about 60 g n n Equivalent to about 2% of the mean penguin body mass of 3. 0 ± 0. 4 kg

n Various Kiwi. Sat 101 transmitters

n Kiwi. Sat 202 transmitter for a penguin or small sea turtle

Materials and Methods n n Devices were programmed to transmit on a cycle of 6 hr on / 18 hr off with a repetition period of 60 s Equipped with a saltwater switch that prevented transmission while under water to conserve battery life The Kiwi. Sat 101 recorded and transmitted time penguins spent at the surface Transmitter life: 84 days with 2 AA batteries

Results n n n A total of 1, 340 daily positions were obtained from the 22 magellanic penguins The mean minimum distance traveled by all penguins was 1, 440 ± 685 km The mean distance covered per day was 23. 2 ± 6. 6 km

Results n n Penguins spent 52. 8 ± 6. 3% of their time at sea submerged Sex-related differences were not found with regard to transmission duration and migratory parameters

Results n n All 22 penguins left Beagle Channel in an easterly direction Most (except for three) penguins traveled around the southeasterly tip of South America into the Atlantic They headed north and migrated along the Argentine coast until transmission ceased Migratory behavior was decomposed into periods of rapid movement in a northerly direction, interspersed with periods, during which the birds remained for some time in a certain area

Migration routes in 2004 n n n n Fips = red (filled square) Flo = green (filled diamond) Fyjima = yellow (plus symbol) Lu = pink (filled circle) Miriam = blue (filled triangle) Silvester = brown (rectangle) Wa. Ru = black (filled inverted triangle)

Migration routes in 2005 n n n n Biggi = black (filled circle) Egregrius = red (rectangle) Eva = brown (filled square) Jennifer = pink (filled diamond) Jupp = blue (filled triangle) Schroder = green (filled inverted triangle) The Boss = yellow (plus symbol)

Migration routes in 2006 n n n n Florian = blue (filled circle) Gimmy = light blue (open rectangle) Kira = brown (filled diamond) Klaus = green (filled triangle) NN 1 = pink (filled inverted triangle) NN 2 = black (open rectangle) NN 3 = red (plus symbol) Whitney = yellow (filled square)

Discussion: Impact of Transmitter? n n The external attachment of devices is likely to have an impact on behavior Likely an increase in hydrodynamic drag, which negatively impacts on a great variety of foraging parameters This effect is more pronounced in transmitters equipped with an antenna, which increases hydrodynamic drag even more After 2005, the position of the transmitters was moved further to the body center

Discussion: Impact of Transmitter? n n All devices ceased transmission during migration A possible reason: n Penguins detached satellite transmitter by biting and breaking the feathers attached to it

Discussion: Migration Patterns n n n Penguins originating from the Falkland Islands (51°S) remained exclusively in the Atlantic Ocean, then migrated northwards One penguin migrated into the Pacific, but headed northwards as well A north-bound winter migration appears to be a general feature for magellanic penguins

Discussion: Migration Patterns (cont’d) n n Due to the temporal and spatial differences in their migration patterns, penguins experience qualitative and quantitative variations in food availability However, nothing is known of a magellanic penguin diet during winter months

Discussion: Migration Patterns (cont’d) n n Northbound migration can be related to decreasing sea temperatures, light levels and progressively impeding planktonic growth in more southerly regions as season progressed Migration is driven by formation and subsequent dissipation of areas with enhanced food availability

Discussion: Human Activity Interactions n n Magellanic penguins are increasingly exposed to human-related activities Prey of the penguins is commercially exploited and population crashes may happen due to the poorly-managed fisheries There are mortalities associated with the fishing itself Example: in Puerto Quequen, Argentina, 100 magellanic penguins die each year as bycatch in coastal fishing

Discussion: Human Activity Interactions (cont’d) n n Oil pollution is a much more obvious effect on penguin survival In 1991, about 15, 000 magellanic penguins died as a consequence of one single oil incident Each year, more than 40, 000 penguins die each along the Argentine coast of Chubut due to chronic oil pollution Magellanic penguin breeding population located in the northern distributional range has decreased a lot over the past decade which greatly indicates harmful interaction with human activities

Conclusions n n Winter migration after molt was satellite tracked for three years Potential impact of transmitters on behavior Northward migration during winter is related to decreasing sea temperatures, light levels, and food availability Harmful human activity interactions include poorly-managed fisheries, fishing gear, and oil pollution n These decrease breeding populations in the northern distributional range

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. Thank you! Questions?