'I'm always looking for the Hows and the Whys and the Whats,' said Muskrat, 'That is why I speak as I do. You've heard of Muskrat's Much-in-Little, of course?'
'No,' said the child. 'What is it?'
- The Mouse and his Child. Russell Hoban.

Go here to find out more.

Thursday, 28 January 2010

Cannon-netting at Miranda - part 3.


When you have about forty wild South Island Pied Oystercatchers (SIPO)jumping around in boxes and the drizzle has been replaced by patchy sunshine, the best idea is to process and release them as soon as possible. In relays, each SIPO passed through the hands of each of the course members, who were shown how to measure and record their vital statistics: wing length, state and number of flight feathers, bill length, approximate age, weight and eye patterns. And of course, details from any leg bands, which, if they didn't have one, they were given. The leg bands, which are usually only recovered if the bird is caught like this or dies, are stamped with the bird's unique number and also an address where the band should be sent.
Other information like the date and place the tag was found, and the bird's condition, cause of death if known, etc., are useful.

And here we come to the point of the exercise. Why is it useful? Why do all this? Well, it's not just about learning about South Island Oystercatchers, or any other specific waders. Although, by gathering information about the shorebirds at Miranda, New Zealand, we can indeed learn a lot about these creatures for their own sakes.

More importantly, we can notice aspects of their health or if their populations are increasing or decreasing and make guesses as to why, when we link this with other data about, for example, mangrove encroachment, predation, and human disturbance of many kinds within New Zealand.

Yet it is more important even than nationally. When we look at information about birds, especially migratory birds like the Godwit, we are registering the influence of other global effects. Certainly we know the massive reclamations in North China and North Korea, where the Godwits and Knots stop for a month to refuel, are removing crucial tidal flat staging posts. Can the birds stop to feed elsewhere? Have they been spotted anywhere else?* What happens if they cannot get quite enough fat laid down for their last hop? Do they fall into the sea? Or do they get to Alaska but not have the reserves to breed successfully? What will happen when the Alaskan tundra melts earlier in the season and the succulent larvae that birds need are already adults flying around when the birds arrive?

The more we understand about the world, the more we can understand ourselves, and where we fit in. And the extent to which what we do on this planet affects the balances between the flora and fauna here, and the significance of these changes.

The birds could be seen as indicators of change.


* No.

Bill length.

Weight.

Flight feathers - number and age, wing length.


Bling.



Above - a juvenile SIPO. Note the eye colour compared with the adult below.

Release. Squawk!

And, if you are unlucky, your shoes will be anointed.

2 comments:

  1. Pardon me but I don't think the word "anointed" was the one you were looking for!
    Useful justification for the process. Given what man has done to this planet it is amazing that so many birds keep on keeping on. We don't make it easy for them. That oystercatcher's beak is amazing isn't it? How many thousands of years did that particular evolution take?

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  2. YP, thanks for the comment. 'Anointed' not appropriate? - as in "smear or rub something with a substance"...? I inadvertently had my shoe under it when I released it. Although I suppose it was more of an ejection than an anointment.

    Re. bill evolution - with a consistent 'pressure' and a large enough population with enough genetic variety, I think the only thing that slows down evolution is generation length. I think that SIPO can breed at 3 years old, so theoretically, bill shape could change in a relatively short time. I remember reading somewhere that certain finches on the Galapagos could be separated out from their forebears (based on a changing bill shape) in only 22 years.

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