Effects of flipper bands and injected transponders on the survival of adult Little Penguins Eudyptula minor

Abstract

Tagging is essential for many types of ecological and behavioural studies, and it is generally assumed that it does not affect the fitness of the individuals being examined. However, the tagging of birds has been shown to have negative effects on some aspects of their lives. Here we investigate the influence of tagging on apparent survival. We examined the effects of flipper bands and injected transponders on the apparent survival of adult Little Penguins by comparing the survival probabilities of 2483 Little Penguins marked at Phillip Island, Australia, between 1995 and 2001 in one of three ways: with bands, with transponders or with both. The design of the study and our method of analysis allowed us to estimate tag loss and ensured that tag loss did not bias the survival estimates. Birds marked with flipper bands had lower survival probabilities than those marked with transponders (with apparent survival probabilities in the first year after tagging of 75% for banded birds and 80% for birds fitted with transponders, and in subsequent years of 87% for banded birds and 91% for birds fitted with transponders). We estimated both band and transponder loss probabilities for the first time, and found that transponder loss probabilities were substantially higher than band loss probabilities, particularly in the first year after marking when the tag loss probability was 5% for transponders and 0.7% for bands. Survival probabilities were lower in the first year after marking than in subsequent years for all birds. Studies of penguins that have used flipper bands to identify individuals may have underestimated annual adult survival probabilities, as banded penguins were likely to have lower than average survival probabilities than those of unbanded birds. The higher annual survival probabilities of individuals marked with transponders indicate that this should be the preferred marking technique for Little Penguins. However, future studies will, like ours, need to consider the higher rates of transponder loss when estimating survival, possibly by double-tagging some birds.

Age‐specific survival and movement among major African Penguin Spheniscus demersus colonies

“…However, any bias is probably of the order of magnitude reported by Dann et al . () of around 5% rather than the larger biases reported in other genera (e.g. up to 30% in Saraux et al .…”

“…, Dann et al . , but see Appendix S1). Long‐term double‐marking studies on African Penguins have not been carried out and efforts are now in place to discontinue flipper‐banding of this species (e.g.…”

Hydrodynamic handicaps and organizational complexity in the foraging behavior of two free-ranging penguin species

“…However, the lack of effects of logger position in little penguins, logger size in Adélie penguins and, surprisingly, flipper bands in little penguins suggests that animal-attached devices do not universally induce such organizational changes in seabird foraging behavior, despite having clear effects on other dive parameters and potentially, for flipper bands at least, fitness outcomes [49][50][51].…”

“…Indeed, dive durations and betweendive durations increased in the flipper band experiment, meaning that the sequential distribution and variance of both dive and surface durations may not have changed, leaving the global structure of the foraging trip unchanged as well. This also suggests that global structural changes in the organizational complexity of dive sequences need not be associated with other changes in foraging behavior, e.g., those induced by flipper bands, that are known to significantly affect survival and reproduction (e.g., [49][50][51]). …”

Population structure and phylogeography of the Gentoo Penguin (Pygoscelis papua) across the Scotia Arc

“…While they have a large breeding distribution, Gentoo penguins also exhibit high levels of natal philopatry and tend to remain within the same archipelagos year-round (Stonehouse 1970;Tanton et al 2004;Ratcliffe and Trathan 2011). However, determining the limits of the species' foraging range over a lifetime is difficult because of ethical, cost, and technical challenges associated with long-term tag or transponder use (Froget et al 1998;Gauthier-Clerc et al 2004;Saraux et al 2011;Dann et al 2014). Previous studies have indicated that Gentoo penguins have a maximum observed dispersal of 276 km during the nonbreeding season in the Falkland Islands (Clausen and P€ utz 2003) and 268 km in the South Shetland Islands (Wilson et al 1998).…”