Hi all, especially Itai, Brian and Don.

This paragraph taken from a recent posting to the
Kenyabirdgroup, notes by Brian Finch.

""""""""""""""""""""""""""""""""
Zimmermann & Turner and Stevenson & Fanshawe were
> unaware of these> western  populations of Athi
Short-toed Lark,> Pangani Longclaw, Taita> Fiscal and
Southern Grosbeak Canary and considered> them only
east of the> Rift in Southern Kenya, but the
populations of all> four species is> considerable in
this strange part of the Mara> ecosystem.

"""""""""""""""""""""""""""""""""'

In the Serengeti ecosystem (which includes the Mara)
to the south of the Mara we have witnessed a
significant increase in records of dry country species
in the past decade and a half.

There is only one 1980s record of Pangani Longclaw
west of the Rift but they are now well established.
Other species that have spread westwards over the Rift
include White-bellied Go-away, Long-tailed Fiscal and
Black-throated Barbet. There are others that may well
be following this trend. Difficult to know if this is
permanent and why, obviously "climate change" is an
easy finger pointer but .........

There is good date from the NCA / Serengeti through
the 70s and 80s so we think these range expansions are
real.

So ... Brain, Don, Dave ... are there old records from
this part of the Mara from the 70s and 80s that can be
used for comparisons ? is there data on habitat
structure changes ? is there any evidence of range
shrinkage to the east or are we looking at species
population increases ? Post breeding dispersal into
habitat that is now suitable and wasn't 20 yeasr ago ?

Lots of questions, all ideas much appreciated.

Tony (Sinclair) comments here please. I'm sure we are
witnessing considerable range expansions and if these
drier than average years continue we should all be on
the alert for other species making this jump
westwards.

regards

Neil


Neil and Liz Baker, Tanzania Bird Atlas, P.O. Box 1605, Iringa, Tanzania.
Mobiles: 0748-509906 and 0748-834273.
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