The Hoanib River Catchment embodied much of what I imagined Northwest Namibia to be: rugged, remote, and harsh. I was unprepared, however, for how stunningly beautiful it was. The early morning and evening light hit the canyon walls and mountain sides at oblique angles, painting the texture of the rocks with new shadows and colors, constantly changing the scenery. This evolving landscape supported an amazing diversity of wildlife and a relative abundance of giraffe.
We have been studying the movement ecology of giraffe in this area, and in the lower Hoanib, we encountered a few of the individuals sporting GPS units. These are the same giraffe that I have been monitoring from afar for the past 2 years and it was a privilege to finally share space with them and experience the rivers that support these desert wanders. Beyond analyzing remotely sensed data, an understanding of these beings requires more intimate perspective, and offered a valuable glimpse into how these giraffe navigate these arid environments
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We first caught glimpse of the Haurosib River as we drove back inland from the barren Skeleton Coast. Descending into the river plain from the surrounding mountains, I was immediately struck by the wide and productive desert riparian zones. An oasis of greenery in an otherwise rusty and tawny landscape, this river system held relatively large numbers of giraffe and other animals tucked amongst the Salvadora persica and Acacia tress. We camped in one such area along the sandy riverbed and set up our tents in the shadow of a large bull giraffe.
The largest town in this area is Puros, which is an eclectic smattering of houses and trading posts on the flat desert along the banks of the ephemeral Huarsib river. In Puros, the river bed meanders across an open plain, but just upstream, it emerges from impressive canyons tucked in forbidding mountains, before branching and disappearing into similar mountains just downstream. Here, water is life but it is elusive, snaking its way in and out of impassable canyons, leaving just enough open area, woody vegetation, and water beneath the earth's surface to sustain the areas' wildlife and people, tucked amongst the dunes. The diversity of environments that giraffe inhabit is not only apparent at the continental scale, but also at the intrapopulation level. I recently returned from a couple weeks in Northwest Namibia where I worked with colleagues to survey giraffe in three different ephemeral river systems that primarily drain into the Skeleton Coast. These tree-lined sandy depressions create arteries of vegetation through an otherwise barren landscape, sustaining life between the infrequent rains. Despite being separated by only a few kilometers - and some formidable mountains - each river system, and the surrounding areas had remarkably different ecological rhythms.
Our surveys began in the areas surrounding the hyper arid Khumib River Catchment, one of the drier and northerly river systems in western Namibia. From the crimson sands of the Marble plains to the barren expanses of the Ensengo and Gomatum, these Martian landscapes provided otherworldly backdrops for giraffe. Perhaps more impressive was the number the thriving Himba communities along these desiccated waterways. I have spent most of the last decade studying giraffe and other megaherbivores in the savannahs of east Africa, so these first few days of surveys in Northwest Namibia gave me a much more visceral appreciation the resilience of these incredible animals and their ability to thrive in some of the harshest landscapes I've experienced. A cool breeze catches the nylon fabric stretched over the 9 foot frame and lifts the kite skyward. This particular kite strains under the additional extra ounces of a FujiFilm FinePix XP80 camera mounted to a picavet rig attached to the kite string. The specialized payload contains a programmed intervalometer which will trigger the shutter every 15 seconds. As the kite is guided around the landscape, it will capture images of the distribution of various plants over the heterogeneous savannah. Drones aren’t allowed here, but we managed special permission to trial kite aerial photography. Coupled with direct observations of feeding giraffes on the same landscape, this birds-eye view can be used to inform our understanding of how giraffes make foraging decisions in heterogeneous browsing landscapes. The distribution of large browsing herbivores is influenced by the distribution of woody vegetation which is influenced by soil nutrients which is influence by distribution and abundance of arthropods, which are in turn somewhat influenced by the distribution of browsing herbivores. Sometimes a different perspective can offer new insights into the processes that give rise to emergent patterns in nature.
I forgot how much I missed salt water. I hadn’t touched the Atlantic Ocean in over two years, and it’s been nearly 5 years since I visited my natal shores on the New Jersey barrier islands. While the sandy beaches, rolling surf, and east coast moonrises rightfully get a fair bit of attention by weekend vacationers, boardwalk cruisers, tanned retirees, and high school summer employees, I love the to chase the tides upstream into the salt marshes.
In the home of the terrapins there’s a relative quietness away from the crashing waves, but soon the gentle lapping of the incoming tides, the song of the redwing blackbird, and the chirp of the osprey provide a different welcoming soundscape. It does not take long to realize why and how these ecosystems are among the most productive on the planet. Saltwater adapted grasses and rich organic silt support incredible diversity and provide critical ecosystem service to those living on the mainland. The life sustained by salt marshes cascades into to other ecosystems from the waterfowl that span continents to the fish that span oceans. I find it incredible how one animal can mean so much to so many. Upon close consideration – and my profession affords me time for considerable consideration (perhaps too much consideration) – I am endlessly fascinated by the role that giraffe play in ecosystems and culture. For the lioness, a giraffe may represent the opportunity to feed the next generation of her pride who lay hungry in the shade of a nearby Balanites aegyptica... For the Acacia senegal tree, giraffe may serve as unexpected but critical pollinator, transferring pollen long distances between foraging bouts and maintaining the genetic diversity of tree species.... For the dung beetle, giraffe provide the raw materials to build a brooding ball to nourish the next generation. For an uncle at a giraffe feeding exhibit at the local zoo, giraffe can represent a shared moment of wonder with his new nephew as they watch that marvelous tongue hoover a lettuce leaf. For an infant in Paris, France, a small rubber giraffe can be a soothing plaything to ease the discomforts of teething. For the elder woman in a community adjacent to Pian Upe Game Reserve in Uganda, giraffe can represent a sense of ecological hope and resilience. As she showed incredible strength to endure years of civil unrest, she also watched as that same conflict decimated the giraffe populations around her community in the mid 1990’s. Through scientifically informed conservation action and dedicated international collaborations, giraffe were reintroduced to the landscape in 2019 and she sang to welcome them back home. These animals served not only as a critical component of this ecosystem but also as a culturally significant totem to neighboring communities. We share the world with such beautiful beings. Today, especially, I encourage you to reflect on the evolutionary marvel of the giraffe, as individuals and as members of vibrant ecosystems. And while your attention is there, I encourage you stay in that moment of beauty and reflect on the poetry of perhaps less iconic organism somewhere in your local surroundings. What does sharing space with that organism mean to you? Let giraffe be a gateway to wonder. For these plains zebra in Ngorongoro, safety is found in numbers, clear visibility, and open landscapes. In the amazingly rich ecosystems of the crater’s plains and savannahs, predator and prey can often be seen in uneasy (at least for the zebra) proximity. The wary equids spend daylight hours taking advantage of the grass growing in the fertile volcanic soil, grazing in relative safety. I suspect it is a dramatically different scenario in the darkness.
Prior to the days of quality cell-phone cameras, I would keep a rugged point-and-shoot camera as a side-arm in a pouch on my belt. During this particular shot, the lions passed so close to the Landcruiser that I wanted a wider-angle perspective, so I put down the telephoto lens and reached to my hip for my reliable Nikon Coolpix for this shot. I find antlers incredibly beautiful and endlessly fascinating. Beyond the elegant curves of ivory and mahogany colored bone, these uniquely cervid protruberances are incredibly diverse in form but remarkably simple in function. Most classically, antlers are essential for combat and conquest during a very short period during the breeding season. The amount of energy and nutrients that contribute to the growth of this deciduous bone is astounding, with some moose antlers exceeding 70 pounds in weight requiring immense investment from their wearer. After the violence of the rut (at least in most temperate cervids), these bones have mostly served their purpose and room must be made for the next year’s headgear. Eventually, the bone is severed by the ebb in sex hormones, and these adornments are unceremoniously shed into quiet snowbanks to be eroded by time or a fortunate porcupine. After the thaw and as the spring flowers begin to blossom, the cycle begins again, and the velvety bone regenerates, oftentimes bigger and more robust than the previous year. A cleverer man might find a powerful metaphor in that process.
Dall sheep usually don’t live in ugly places. Denali National Park is certainly not an exception to this rule. Those who spend time in Denali experience nature at an incomprehensively large scale. It’s the kind of place that makes you feel small in a good way. And Dall sheep always have the best views.
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AuthorMichael Brown Archives
December 2022
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