Nature’s cycles and its effects on Birding in St Lucia.

The Eastern shores, Isimangaliso Wetlands Park during a wet period: A mosaic of Wetlands with Lake St Lucia in the far distance.

Like the rest of Southern Africa, St Lucia typically alternates between prolonged dry spells and wet spells according to the El Niño and La Niña weather phenomenons.

These opposite extremes, drastically change the face of the landscape with resulting changes in birdlife.

The most recent El Niño episodes occurred from 2014 until 2016 and again in 2018/19. The associated drought which reached its peak in 2016 was one of the worst in recorded history. The wetlands had mostly disappeared with a couple of exceptions, and even these were shallow and small in size. As a result wetlands waterfowl were few and far between. 

Lake St Lucia dried up to the extent that it was possible to walk right across the lake in some places. A walk on the dried lake bed in places such as False bay revealed thousands of sun-parched fish carcasses. Remaining fish were concentrated into the last remaining deeper pools in the lake which made easy-pickings for the vast flocks of Pelican (both Great white and Pink-backed) which came to take advantage of the easy food source. Large flocks of these birds could be seen soaring above the lake most days. Also during this time almost every tall conifer tree in St Lucia was a hotly contested perch for Pink-backed pelican to sleep on overnight. It was interesting to watch them jostling for position at dusk every evening, dive-bombing each other kamikaze-style to knock their contester off his/her perch. In the time period when the lake was shrinking, vast shallow areas attracted large flocks of both Greater & Lesser flamingo which could be seen as vast whitish/pink swathes on the edges of the lake.

Apart from the birds, the dry lake and wetlands also had a major impact on the local hippo population. Competition for remaining water was severe and many battle-scarred and wounded hippo could be seen. Many (especially young sub-adult bulls) took refuge in the forest during the day as an alternative to water to try keep cool whilst staying out of the way of dominant bulls. It was a risky time in St Lucia as a result with some hippos sleeping in gardens and lodge grounds during this time.

In 2017, Southern Africa enjoyed a years respite from the grips of El Niño with Zululand experiencing a wetter year than other parts of the country. All of a sudden the St Lucia area had large influxes of African cuckoo-finch and Harlequin quail and even the odd Black coucal (all unusual birds for the area). In the Mkhuze section of the Isimangaliso Wetlands Park, huge flocks of Red-billed quelea (attracted by good seeding grass) could be seen flying in their amazing murmurations. In certain areas of Mkhuze, every acacia tree/sickle bush was coated with dozens of nests. The thousands of nesting quealeas in turn attracted large congregations of Lesser spotted eagle (another uncommon bird for the area) with groups of over 50 birds seen in areas with quealea nests. 

As often happens in wetter years after prolonged drought, the area also  experienced insect ‘plagues’. The first was seen in the nearby Hluhluwe/Umfolozi game reserve in 2017 where a plague of army worms marched across the landscape, devouring almost every leaf off every Tamboti tree in their path. Meanwhile, in St Lucia in 2021 a plague of Celtis leaf beetle did the same to all the White stinkwood trees, devouring almost every leaf off every White stinkwood in the forests. These edible larvae formed dense clusters on the trunks of trees, buildings and surrounding areas before pupating into the beetles themselves. Needless to say, this rich food source attracted many insectivorous birds to the area. African emerald cuckoo, usually uncommon in St Lucia, were seemingly everywhere. Birding surrounding the White stinkwoods was absolutely amazing and usually secretive birds such as Green malkoha just sat out in the open, seemingly too engorged to care.

With the drought ending and Southern Africa entering a strong La Niña episode in 2020 (with associated high rainfall) the Lake St Lucia estuary mouth has breached twice in recent years (the first artificially to alleviate flooding upstream and the second naturally) . The initial few weeks after the breaches- effectively like a plug being pulled on the lake system- were an absolute amazing wildlife spectacle to witness. The rush of water out of the mouth into the ocean pulled thousands upon thousands of freshwater fish, an assortment of snakes and even crocodiles onto the surrounding beaches. This fish feast attracted a big variety of piscivorous birds and scavenging birds to the area. The beaches either side of the estuary mouth were literally packed with an unusually high quantity of terns. At the estuary mouth itself, multiple Bull sharks could be seen hunting at any one time- in amongst big crocs! The crocs lay facing into the outgoing current, snapping up any fish that swam into their open jaws. Quite outrageously, someone even photographed a croc devouring a baby bull shark caught in this way! With the estuary mouth open and freshwater fish washing up on the beaches most low tides, Palmnut vulture have become a regular sight on the beaches adjacent to the mouth in recent years- scavenging on the washed up fish carcasses. The open estuary mouth has also turned up some interesting rare vagrants in recent years such as Crab plover and African skimmer.

​The rains arrived properly in 2021/2022 with 2022 being the wettest year recorded since 1953- a whopping 2000mm of rainfall recorded in St Lucia! As a result of the high rainfall, the wetlands within the Isimangaliso Wetlands Park have returned and so have the waterfowl. Birds such as African pygmy-goose, White-backed duck, Lesser moorhen, Dwarf bittern and a bevy of other more common waterfowl have returned to the area. Birds such as Rosy-throated longclaw too are more common now that the Wetlands have returned. Lake St Lucia has also filled to the brim.

Latest predictions predict that we may enter another El Niño period later this year. Will be interesting to see what effects this will have on the area and the birds again!

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