Jan. 11, 2011, "Reliability of flipper-banded penguins as indicators of climate change," Nature letter
"In 2007, the Intergovernmental Panel on Climate Change highlighted an urgent need
to assess the responses of marine ecosystems to climate change1. Because they lie in a high-latitude region, the Southern Ocean ecosystems are expected to be strongly affected by global warming. Using top predators of this highly productive ocean2 (such as penguins) as integrative indicators may help us assess the impacts of climate change on marine ecosystems3, 4.
Yet most available information on penguin population dynamics
is based on the controversial use of flipper banding. Although some reports have found the effects of flipper bands to be deleterious5, 6, 7, 8, some short-term (one-year) studies have concluded otherwise9, 10, 11, resulting in the continuation of extensive banding schemes and the use of data sets thus collected to predict climate impact on natural populations12, 13. Here we show that banding of free-ranging king penguins (Aptenodytes patagonicus)
impairs both survival and reproduction, ultimately affecting population growth rate. Over the course of a 10-year longitudinal study, banded birds produced 39% fewer chicks and had a survival rate 16% lower than non-banded birds, demonstrating a massive long-term impact of banding and thus refuting the assumption that birds will ultimately adapt to being banded6, 12.
Indeed, banded birds still arrived later for breeding at the study site and had longer foraging trips even after 10 years. One of our major findings is that responses of flipper-banded penguins to climate variability (that is, changes in sea surface temperature and in the Southern Oscillation index) differ from those of non-banded birds. We show that only long-term investigations may allow an evaluation of the impact of flipper bands and that every major life-history trait can be affected, calling into question the banding schemes still going on. In addition, our understanding of the effects of climate change on marine ecosystems based on flipper-band data
should be reconsidered."
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Jan. 12, 2011, "Data from banded penguins suffer from fatal flaw," arstechnica, Yun Xie
"A paper in a recent issue of Nature
reveals that flipper-banded penguins live quite differently than unbanded birds....
The behavior of banded penguins could very well be a reflection of a metal accessory that potentially injures flipper tissue and impedes swimming,
rather than environmental changes....
Over 10 years of observation, they found that banding influenced survival and breeding rates,
which would skew data collection.
On top of that, banding could be exceptionally harmful for vulnerable birds like those recovering from oil spills. After an oil spill off Cape Town in June 2000, roughly 20,000 African penguins were rehabilitated and flipper-banded before being released. Those penguins might have done better without the added burden of a flipper-band. Since there are alternatives to flipper-banding, it could be worthwhile to invest in newer techniques for the sake of obtaining more reliable data and avoiding damage to wildlife....
Over the decade, banded birds were less successful in breeding."....
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A Nov. 2012 published penguin study
actually took place 7 years ago, in 2005. It was only 4 weeks in duration and inserted metal cable into the penguins' flesh ("to the lower back"), two factors which would likely disqualify the study per the Jan. 2011 Nature cover story. Further, per Nature, penguin foraging behavior changes because of banding so it's not valid to blame foraging changes on CO2 (as Nov. 21 study suggests though metal was inserted in animal's back rather than its flipper). Nature: "Banded birds still arrived later for breeding at the study site and had longer foraging trips even after 10 years."
Nov. 21, 2012, "Activity Time Budget during Foraging Trips of Emperor Penguins," plosone.com
"Methods
Field Experiments
The field study was conducted at the breeding colony at Cape Washington (74°39′S, 165°24′E) during the chick-rearing period from 26 October to 24 November 2005.Fourteen birds departing the colony were captured near the edge of the colony. Data loggers were attached to the central back feathers using waterproof Tesa™ tape
(Beiersdorf AG, Hamburg, Germany)
and stainless steel cable ties. Eleven birds were equipped with acceleration data loggers (W1000-PD2GT: 22 mm diameter, 122 mm in length, 73 g mass in air or W1000L-PD2GT: 27 mm diameter, 128 mm in length, 101 g mass in air, Little Leonardo, Tokyo, Japan) which recorded depth (1 Hz), temperature (1 Hz), speed (1 Hz), and two axes of acceleration (16 Hz, respectively). Three birds were equipped with 3-D loggers (W1000L-3MPD3GT: 26 mm diameter, 174 mm in length, 120 g mass in air, Little Leonardo Ltd, Tokyo, Japan) which recorded depth (1 Hz), temperature (1 Hz), three axes acceleration and three axes geomagnetism (8 Hz, respectively). The devices were set to start recording 4–96 h after deployment by the preset delay timer. According to the limitation of memory size, the logger cannot cover the whole foraging trip of each individual. The variation of recording start time (4–96 h) enabled us to record all phases of the foraging trips. VHF transmitters (Model MM130, ATS, Isanti, MN, USA) were
attached to the lower back with cable ties. Body mass was measured to the nearest 100 g at deployment and recapture, using a balance (Pesola 50 kg). Mass of the devices deployed were less than 1% of the body mass. Methods of the field study and the deployments of loggers were described in detail in [25]."...
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