Friday, 11 August 2017

The demise of F-Nord lake

F-Nord lake is the best birding site in Nouakchott, Unfortunately it is being drained and I suspect it will be no more in two weeks.

This is a tragedy. There are saline pools all over the west of the city and I can understand why they are drained. They pose a threat to the housing in large areas. However there is a thin line running north to south in the middle of the city where freshwater appears on the surface in a few places. The two main places are F-Nord lake and Cinquieme Gardens.

F-Nord lake has grown and matured over ten years. It is fed by filtered sea water which is fresh by the time it reaches this far inland. It is almost certainly also fed by waste water from human activity. There is very little sewage collection in the city. However the water appears perfectly clean. It is cleaned by the soon-to-be-no-more reed beds as well as filtered by the earth. In this sense it is man-made.

I presume the drainage is part of a blanket policy to drain the city of lakes and pools or may be it is a private owner doing this.

There is very little I can do without local support. My friend Dr Mohamed Vall arranged for two of his students to do a study and report for their degrees but local awareness of the lake's value is very low. I wrote to Wetlands International three months ago but got no reply. 

I am very upset. This lake has had the only breeding Eurasian coot south of the Sahara in west Africa. It has been the most northern breeding of African swamphen. It has the only breeding moorhen for 200 kilometres. It has attracted water birds normally not seen further north than the Senegal river. I have seen dwarf bittern, little bittern (african sub species) and Allen's gallinule, once in each case.

Marbled duck and black-necked grebe wintered there.

Last Saturday it was immediately obvious the water levels were well down and the pumps were humming.

black-winged stilt

I have never seen more than two black-winged stilt at the site. This time there were ten. A sign that the levels temporaily suit them.

moorhen

The moorhen, coot and African swamphen were still there but I doubt for much longer if or when the reeds start to dry out.

white-faced whistling duck

I don't think white-faced whistling duck has ever been seen as far north as Nouakchott in West Africa but they were present last Saturday driven north by the rains further south at this time of year. I saw two of them standing on a small island that is newly in existence due to the lake level falling.

blue-cheeked bee-eater

Blue-cheeked bee-eater were back. I now know this is a July to December resident and not an all-year bird as erroneously declared in the maps of Birds of Western Africa. Indeed these were the first ones I and Mohamed Vall have seen in our travel throughout Mauritania since December and that includes the south. The only exception was a single migrant heading north in April.

five white-faced whistling duck

After a while I worked out there were five white-faced whistling duck present. 

wood sandpiper

I counted 30 wood sandpiper. This is my largest number at any site in Mauritania. I presume many are on autumn passage.

grey heron with little grebe

I had wondered what the grey heron do for food at this site. There are no fish. I witnessed a grey heron grab a little grebe. It took five minutes trying to both suffocate and drown the catch. The large little grebe population is over-exposed at the moment as diving into deeper water is no longer possible.

blue-cheeked bee-eater

I decided to walk partly round the lake to get a closer look at the grey heron. I passed more blue-cheeked bee-eater on the way.

little grebe now half swallowed

I was surprised the little grebe was not too large but it wasn't.

almost all swallowed

The grey heron succeeded in eating it all.

many wood sandpiper

I am not sure I will visit the lake again. It is too distressing. I am hoping for a thunderstorm to give it a temporary reprieve. However, thunderstorms are very irregular in Nouakchott which is right on the northern edge of the Sahel.

At least I have good records of what can be in Nouakchott.


Species seen at F-Nord lake on  5th August
White-faced Whistling-Duck  
Little Grebe  
Grey Heron  
Western Reef-Heron  
African Swamphen  
Common Moorhen  
Eurasian Coot  
Black-winged Stilt  
Spur-winged Lapwing  
Kittlitz's Plover  
Kentish Plover  
Common Sandpiper  
Marsh Sandpiper  
Wood Sandpiper      
Common Tern  
Speckled Pigeon  
Laughing Dove  
Little Swift  
Blue-cheeked Bee-eater  
Crested Lark  

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