BirdLife Botswana AGM 2010

Please make a note of 15th May as that will be the date for our AGM, which will be held at Harold and Geraldine Hester's residence, Mogorosi, Plot 30a Notwane. The meeting will start at 18:00 and will be followed by a light supper. Closer to that date we will circulate the agenda and other details.

Water reaches Savuti Marsh

Water in the Savuti Channel reaches Savuti Elephant Camp (Photo courteousy Orient Express Safaris)

The high flood levels in northern Botswana during mid- and late-2009 caused great excitement and speculation, with the Boteti River in particular being the focus of attention for many people. However, the highest water levels in decades in the Kwando led to the hope and belief that the Savuti Channel would at last flow again. Indeed, the water soon reached Wilderness Safaris ‘Savuti Camp’ in the Linyanti concession, but as it approached the western boundary of the Chobe National Park it slowed down and lost momentum (most of the water having bypassed the mouth of the Savuti at Zibadianja, and flowed down the Linyanti and into the Chobe River). Eventually the water stopped several kilometres from the Savuti Marsh.

Much to the surprise of many people, the channel started flowing again in earnest in December, possibly due to heavy unseasonal rains that fell in mid-2009, as well as good local summer rains. By mid-January, the water had flowed past the safari lodges at Savuti and was close to the top end of the marsh.

The 2010 floods promise to be above average, with water levels in the Zambezi and Chobe systems having already risen considerably. With plenty of water remaining from 2009, there is a high probability of the Savuti Marsh being seriously inundated later this year. It is entirely possible that Savuti will once again become one of Africa’s most spectacular wildlife areas. Watch this space!

Will Lake Xau fill?

The flow of the Okavango’s waters down the Boteti River this year have been nothing short of spectacular, with the front of the flood approaching Rakops (over 200km from Maun) at present.

While predicting the future is fraught with all sorts of risks, it seems likely that it is a question of when, not if, the water will once again reach Lake Xau, which is the terminus for the Boteti. This assumes of course that Debswana will remove the structures they built previously to channel water into the Mopipi Dam, but given their recent track record (where they removed the bund blocking the Nhabe Channel leading to Lake Ngami), this looks likely. During wetter decades, Lake Xau was a substantial waterbody, and supported spectacular birdlife; the front cover of Smither’s 1964 Checklist of Birds of the Bechuanaland Protectorate depicts a Gull-billed Tern flighting over Lake Xau, and this is the type of rarity that may well turn up at the Lake again when it floods.

Since the Lake has been dry for several decades now, the lakebed has grassed over, and it is currently not unlike Lake Ngami was before the recent floods. Lake Xau is also similar to Lake Ngami in being a nutrient sink with rich soils that, when flooded, will result in nutrient-rich, eutrophic waters in an otherwise dry area. Lake Xau will almost certainly attract and support a diverse suite of waterbirds – in large numbers – when it finally floods. However, it will not be a destination for ‘armchair’ birders – the location is quite remote, there are no facilities in the area, and access will be difficult. For serious birdwatchers, though, it will be worth watching this Blog for updates on the status of the area.
View of the dry bed of Lake Xau (in distance) from Kedia Hill

Interesting sightings from Tachila

Tachila Nature Reserve, near Francistown, is a new privately run wildlife sanctuary that aims to provide opportunities for environmental education for schoolchildren from throughout the country. It is also a worthwhile birding destination, and BirdLife Botswana Board member, Nicky Bousfield (who has been the driving force behind the establishment of the reserve)sent in the following highlights recently:
"The following are some of the interesting sightings from Tachila:
Short-toed Rock-Thrush (eastern race, with uniform slate-blue crown) Monticola brevipes pretoriae
Freckled Nightjar Caprimulgus tristigma (this bird is marginal in eastern Botswana)
Black Stork Ciconia nigra (uncommon in Botswana)
Boulder Chat Pinarornis plumosus (marginal in Botswana)
Bronze-winged Courser Rhinoptilus chalcopterus
Three-banded Courser Rhinoptilus cinctus (marginal in Botswana)
Yellow-billed Egret Egretta intermedia (uncommon in eastern Botswana)
Yellow-billed Egret (Photo: P Hancock)

African-Fish-Eagles are breeding at Tachila for the third year in a row. Other raptors seen from time to time include Bateleur, African Hawk-Eagle, Black-chested Snake-Eagle, White-backed and Lappet-faced vultures".

Ringed Pratincoles at Lake Ngami

One of the ringed pratincoles (Photo: K Oake)

An observant Maun birder, Ken Oake, recently spotted two Collared Pratincoles with rings (bands) at Lake Ngami, and managed to get a clear photo of one of them. Unfortunately the number on the ring is not legible, making this a somewhat tantalising observation as we cannot be certain of the origin of the bird. It is most likely that it was among the 61 Collared Pratincoles ringed at the Lake during an AFRING training course in December, 2005, and if this is the case, it would mean that the pratincoles are returning to this important site. Only 283 Collared Pratincoles have ever been ringed, so it is great to get a resighting of one of them, even if the information is incomplete.

Birders at Lake Ngami should also keep a look out for other bird species with rings - for example, a large number of Kittlitz's Plovers were ringed there during the AFRING course, and none of them have been re-sighted or recovered to date.

New (overlooked) record for Botswana bird list?

During the Peterhouse School scientific expeditions to Botswana between 1966 and 1970, schoolchildren under the supervision of Peter Ginn (well-known as the editor of ‘A Complete Book of Southern African Birds’) collected bird specimens from the Makgadikgadi area. During one of these outings, a gull that was collected in the Nata area, in the company of Grey-headed Gulls, turned out to be an exciting find. Once the group had returned to Zimbabwe, the gull was tentatively identified by Mr Stuart Irwin from the Natural History Museum as Larus novaehollandiae. This was subsequently confirmed by Messrs CW Benson and PR Colston at the British Museum of Natural History.

When Larus novaehollandiae was later split, the nominate race in Australia retained the name L. novaehollandiae and the southern African birds became L. hartlaubii. This species is restricted as a breeding bird to the coldwater coasts of Namibia and the Western Cape, and sightings inland are quite unusual.

However the interesting thing about this observation is that Larus hartlaubii does not feature on the Botswana bird list. There is no mention of it in the Bird Atlas of Botswana – this ‘bible’ for birds in Botswana included historical data on our birds as well as observations spanning the decade 1980 to 1990. Could this species have been overlooked?

It would be interesting to know the whereabouts of the specimen collected by the Peterhouse expedition, to confirm its identity. Anyone who knows anything about this observation is invited to comment below.