We did the monthly count of House Crows going to roost in Malindi 
followed by a night time count of roosting terns on Sabaki River Mouth 
on Saturday night (every full moon for maximum light for night count - 
for anyone who's interested in joining us..). This time numbers exceeded 
anything I've seen before by a looooong way - except perhaps the very 
first time we discovered the tern roost as I think now I hugely 
under-estimated it then.

First the crows- numbers are continuing to increase. We counted over 
2,200 House Crows this time and that from just one count point (we 
didn't have enough counters to cover two sites). End of last year we 
counted about 1,400 so either there's been a lot breeding in the past 2 
months or an influx of birds from somewhere, or their flight route has 
changed so that we were able to see more of them (it was very windy 
which probably affected this).

The terns. UNbelievable. As we walked along the river bank still some 
5-600m from the mud flats we could hear this intense chattering and as 
we reached the edge of the flats where the mangroves have started to 
grow along the bank we saw our first 'flock' of Saunders' Terns (clearly 
v small and with a high pitched chattering). In that one flock we 
estimated several times, counting the number of birds in a scope view / 
the number deep x across in a section and then multiply it up across the 
flock. Very densely packed much more so that in the day time but clearly 
visible in the moonlight (just as well they're white against a black mud 
background!).... literally carpets of them and we ended up with a rough 
figure of 35,000 birds in just that first flock. As we went further out 
on the mud and looked, the immenseness of the number of birds started to 
hit home. They were packed in and stretching right along in front of the 
mangroves, clearly sheltering from the quite strong wind, and the flocks 
just went on and on and on and on. Every now and then a section of the 
flock would take off - and it would look like smoke swirling around in 
the moonlight. Quite incredible.

We found some mud where the terns had clearly been roosting earlier 
before moving to where they were now - obvious from the smattering of 
droppings - and estimated the number of birds roosting in a square metre 
from the number of droppings counted (I'm not sure if this is a protocol 
that has been used / studied by anyone anywhere - if anyone is aware, 
please let me have refs for it). Using this multiplied by the area 
covered by the terns gave estimates ranging from 400,000 to 1.6 million 
depending on the density of droppings counted. Overall, from trying to 
get a figure from the various methods of counting, I reckon there was a 
good 500,000 birds roosting at Sabaki River Mouth on Saturday night, 
possibly more. A truly amazing sight.

Colin

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~~~~~~~~~~~~~~~~~~~~~~~~~
Colin Jackson
Director
A Rocha Kenya
PO Box 383,
Watamu, 80202
Kenya

Eml: colin.jackson@arocha.org
Tel: +254 (0)20 233 5865 (wireless)
      +254 (0)42 23 32023 (landline)
Cell: 0722 842366

For more information:
www.arocha.org
www.assets-kenya.org
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