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Leg Flagging Phalaropes

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Subject: Leg Flagging Phalaropes
From: "Dean Portelli" <>
Date: Thu, 21 Nov 2002 19:29:35 +1100
Assuming the phalaropes were actually caught and flagged, in my opinion it was a poorly made decision on the banders' part to leg-flag this species as one of the feeding methods they employ is to spin around in a circle while floating on the water's surface. In this situation a flag would obviously cause extra drag on one of the bird's legs which may impair its ability to forage efficiently (unless it can learn to correct for the extra drag). Foraging efficiently can obviously have an impact on survival during migration as enough reserves need to be accumulated to complete the journey, it may be that only a small reduction in foraging efficiency is enough to significantly reduce the bird's ability to accumilate sufficient bodily reserves to see it through migration etc (but again we don't know this for sure! in fact we know very little for sure but my personal view is to ere on the side of caution) - if marking these birds, to be observed presumably in their breeding grounds to know where they come from (as they are seen rarely here) was necessary then colour-bands may have been a better alternative. In fact colour-bands may be a better alternative for all waders as it is the flag 'attached' to the band that seems most likely to be causing the discomfort observed in some small waders - I have seen this discomfort personally (with Red-Necked Stints including birds limping, favouring their unflagged (metal-banded) leg, not using their flagged leg at all and hopping instead) and also examined birds carrying flags in the hand to verify that the band does not move as freely along the leg as a normal band as it is weighted at one end. As for leg flagging waders in general: I hate to dwell but would like to add that based on the repeated observations of a number of people of small waders experiencing discomfort or some sort of problem with leg flags (even if some are false - I have seen it myself) I would like to see a review of the practice to properly investigate this issue (particularly leg-flagging versus normal colour-banding if the issue is the flag, which is something that needs to be resolved, I am not arguing here that there is no merit in marking the birds - if people are going to respond to this message PLEASE stay within the context of what I am actually saying - no reading between the lines!). It is in the best interests of the birds but equally important the best interests of the scientists to review leg-flagging, as the methods that are employed to research the behaviour of animals should have the least impact on the behaviour of the research subjects as any impact a method has on the subject can be a confounding factor in the research and may lead to a less than ideal picture of what the birds are actually doing. For example if marking methods do indeed reduce survival then any study examining survival as a demographic parameter will have results skewed by the research method. To take another example, to look at weight loss during incubation the number of times the bird is removed from the nest and weighed may increase the weight lost by those birds compared to undisturbed birds as the activity and stress levels of the handled birds are greater, hence the research would give figures that are above average for the species. This applies to basically everything that somebody studies (including observational work where a human observer is watching birds), so scientists should (and many do) validate their research methods to make sure they are not confounding their results - I think there is sufficient anecdotal evidence to warrant this for leg flagging, because if there are injury/mortality issues they apply equally to the welfare of the birds as they do to the integrity of the research.

For those who seem to want to defend banding without at least objectively thinking about things first, well before you blast me as a Bennet & co - I am a bander, but I like to at least try to view things objectively and as a bander am concerned about the welfare of the birds that are being banded, especially the ones I band.

Cheers, Dean Portelli





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