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AGULHAS LONG-BILLED LARK: THE HIDE-AND-SEEK CHAMPION

Posted on the 15th November 2021

Hide-and-seek champion

(This article by Dr Alan Lee first appeared in the BirdLife South Africa e-Newsletter: November 2021).

Amazing predator sightings filled the five days in mid-September that I spent in the Overberg helping Sanjo Rose with field work for her Master’s degree. On arrival at our base at Haarwegskloof Renosterveld Reserve, we quickly located the resident Jackal Buzzards nesting in a grove of gum trees. An orientation walk that afternoon resulted in the first of many Black Harrier sightings and a few days later, regular activity and food drops at a certain location suggested a nest with chicks. Cape Vultures from the Potberg colony nearby drifted lazily overhead. A drive to bolster the pentad list added Black-winged and Yellow-billed kites and a splendid sighting of a Martial Eagle. Another special morning started with dawn views of a Spotted Eagle-Owl perched splendidly on a bitter aloe and progressed to a potentially exciting encounter between a Secretarybird and some Helmeted Guineafowl. The Secretarybird, though, settled for locusts instead.

Non-feathered predators seen included three mongoose species – Cape grey, large grey and yellow – while camera traps recorded caracals, African wild cats and genets. Perhaps the only predators of birds that I didn’t see were snakes, although various species had been recorded in the area. Other wildlife that would happily snack on eggs includes bushpigs and baboons. And as evidence that predators were active, walks in the reserve often turned up tufts of feathers of birds that had become protein for some other creature.

My mission in the Overberg was not, however, to spot raptors or predators but to assist Sanjo with her research into the Agulhas Long-billed Lark. Previous work done at Haarwegskloof by Celeste de Kock showed that the species was fairly abundant in the area, while atlas data suggest that it is doing rather well over the 14 years that the project has been running; at least there have been no declines in the population.

The Overberg is one of the most transformed landscapes in the Western Cape; the rolling hills once covered by renosterveld are now intensively managed agricultural land that produces tonnes of maize, wheat, canola, wool and lamb chops. Bakkies and trucks race along roads that switch from dust to mud from one day to the next. Patches of indigenous vegetation are a minimal component of the landscape. So why are birds so abundant and why is the region so species-rich?

By comparison, before arriving in the Overberg I’d been in the Tankwa Karoo National Park, where the pentad at Elandsberg had produced 39 species in three days of comprehensive birding effort. Haarwegskloof gave me a final pentad tally of 85, albeit with an extra day of effort, and the Potberg pentad of De Hoop Nature Reserve had produced 50 species in an afternoon of marginal effort. And while it’s true that the Overberg receives far more rainfall than the Tankwa, on this occasion the latter had benefited from good winter rainfall and put on the most spectacular flower show I’ve ever seen. Nomadic bird species – Grey-backed and Black-eared sparrowlarks, Yellow and Black-headed canaries and Lark-like Bunting – were particularly abundant.

But still, given the transformed landscape and high diversity and abundance of predators, how do regular birds survive – and even thrive – in the Overberg? Experts here suggest that the remnant patches of renosterveld combined with the adjacent high-productivity terrain may be the key. So far, we still can’t say conclusively that the birds (and our target lark in particular) are not nesting in the transformed landscape.

Interestingly, Warwick Tarboton’s book on nests and eggs does not include an entry for the Agulhas Long-Billed Lark. That there are so few nest records for such an abundant bird is quite astounding, but it does suggest that from a hide-and-seek perspective this lark is the champion. During our first field season in 2020 we had no idea what we were looking for; our nest searches had to be guided by the nests of other long-billed lark species. Our first attempts with Vincent Ward and Susan Miller were unsuccessful, although we did catch a few females with brood patches, indicating breeding (the species is also under-represented in the SAFRING database). So how could we get to the bottom of their breeding strategy? Sanjo’s project, like those before it, is focusing on data that will provide statistical results that can be written up as a thesis; specifically, occurrence in the landscape. A far trickier chapter aims to describe nesting location and success. I wasn’t sure it would come to fruition, but at the end of 2020 Sanjo’s extraordinary, dedicated efforts in the field had finally produced for her the first nests.

Now I was there to help again. Unbelievably, beginner’s luck was on my side and I found two nests on my first full day in the field. I spent the morning with a male, foolishly falling for his distraction display until, some hours later, I realised I was being taken in and started to move on. I couldn’t believe my luck when, driving into an adjacent territory, I spotted a male with a caterpillar in his beak. A significant amount of time and patience later, the female confirmed the delivery spot: incredibly in the middle of the track! Nestled in the swathe of annuals was a well-concealed nest with two chicks about 10 days old. That afternoon, a patient walk and a good dose of persistence would bag me my second nest, which contained three dainty speckled brown eggs. Unbelievably, I’d walked right past it during my first pass through the suspected location.

This was going to be a breeze! Except my luck was up. I spent hours following larks over the next three mornings but came up empty handed. The Agulhas Long-billed Lark had reclaimed its crown as hide-and-seek champion. Will Sanjo and her team of assistants be able to take it back this breeding season? Stay tuned for the next exciting update, or get involved by taking a trip to the Overberg and joining the game. Every nest is a special event.

- DR ALAN LEE, EKAPA SCIENCE AND INNOVATION MANAGER
 

COMMENTS

2630
STEVE (posted: 2021-11-24 10:44:59)
I have been involved with this years project, and although many hours spent in the field no nests were found, but the encouraging aspect was that I found a lot of larks in pairs, feeding and close together. There is a definite incline in numbers of these larks over the last 5 yrs I have been birding around the Napier wheatbelt region…..but they still remain the champions at hide and seek!