Field notes from Fairhill Nature Reserve, Western Cape province, South Africa, part 1: the common eland (Taurotragus oryx)

Fairhill Nature Reserve (200 hectares) lies at the western end of the Agulhas Plain. The substrate is calcareous sand and limestone, and the vegetation is intermediate between strandveld and fynbos.

The property was owned and operated by Val Deverson.

Over several visits around 2000-2002, I became familiar with the natural history of this reserve, and also transcribed what Val Deverson herself had observed at various times.

I noted the following during a visit in mid-August 2001, when the population of the common eland consisted of seven, plus one new infant.

RECOVERY OF VEGETATION FROM WILDFIRE

Wildfire had swept part of this property on 30 December 2000, eight months before this visit. It had been fanned by a gale from the sea at about 8 am, before the day's hot weather set in, and this produced flames only 2.5 m high, but horizontally inclined, in the fynbos/strandveld.

Under these conditions, the fire had been uncontrollable by a team of several fire engines. Val Deverson's house was saved only by virtue of backburning the farmyard and last-minute hosing down of the building.

Fortunately, all individuals of the common eland had happened to be near the shore, so that the fire swept away from them, inland.

About half of the tall shrubs in the path of the fire had had their foliage actually combusted. However, in the other half the leaves had been killed without being combusted.

For the first two weeks post-fire, all of the individuals of the common eland had eaten a staple diet of toasted leaves (probably mainly Pterocelastrus tricuspidatus), despite the continued availability of green leaves of the same spp. in the unburnt parts of the property. Presumably this preference reflects the depletion of the anti-herbivore chemical defences in the toasted leaves.

As soon as the graminoid plants appeared in the post-fire succession, the animals had immediately started to eat these. They had routinely and systematically grazed up and down the burnt area as it recovered its greenery, and appeared to be in good condition on this fare.

By the time of my visit, the herbaceous regeneration was about 10 cm high; the woody plants, which were regenerating vegetatively from the base, had new foliage about 30 cm high, and up to 50 cm in the case of Euclea racemosa.

My commentary:
I infer that the common eland preferred post-fire regeneration of graminoids, but in the interim preferred toasted leaves over the living leaves of the unburnt plants of the strandveld, which are evergreen.

The vegetation in Fairhill Nature Reserve, 8 months after an intense fire, had the following composition, based on my own observations in August 2001.

What I found most noteworthy was the lack of germinative N-fixing plants, including Aspalathus.

The ground that remained bare of foliage was 60% or less of the area.

I list the species in decreasing order of foliage cover, in the regenerating stand.

• Ficinia ramosissima? (https://www.inaturalist.org/taxa/569401-Ficinia-ramosissima) 8%
• Ficinia with tufted growth-form 7%
• Thamnochortus fruticosus? (https://www.inaturalist.org/taxa/595315-Thamnochortus-fruticosus) 5%
• Psoralea bracteolata 4%
• Pterocelastrus tricuspidatus (https://www.inaturalist.org/taxa/526208-Pterocelastrus-tricuspidatus) 3%
• Massonia longipes (https://www.inaturalist.org/taxa/862426-Massonia-longipes) 2%
• Euclea racemosa (https://www.inaturalist.org/taxa/526223-Euclea-racemosa) 2%
• Trachyandra ciliata 1.5%
• Phylica dodii abundant small individuals, including both seedlings and vegetative regeneration, some already beginning to flower despite being only up to 10 cm high (https://www.inaturalist.org/taxa/591995-Phylica-dodii) 1%
• Satyrium carneum robust but still at stage of leaf-rosette (https://www.inaturalist.org/taxa/528807-Satyrium-carneum) 1%
• Cyperaceae, unidentified 1%
• Babiana sp. (probably https://www.inaturalist.org/taxa/559365-Babiana-nana) in flower, in aggregations of about 20 individuals 0.5%
• Olea exasperata (https://www.inaturalist.org/taxa/578517-Olea-exasperata) <0.5%
• Searsia lucida (https://www.inaturalist.org/taxa/593894-Searsia-lucida) regenerating vegetatively, up to 0.5 m high <0.5%
• Searsia laevigata (https://www.inaturalist.org/taxa/493489-Searsia-laevigata) regenerating vegetatively, with vigorous fully-green foliage although only up to 20 cm high <0.5%
• Ehrharta sp. (possibly https://www.inaturalist.org/taxa/409471-Ehrharta-villosa) <0.5%
• Orchidaceae, unidentified sp. <0.5%
• Iridaceae, unidentified <0.5%
• Gazania sp. (possibly https://www.inaturalist.org/taxa/567911-Gazania-pectinata) <0.5%
• Cotula discolor <0.5%
• Nemesia sp. with a few flowers visible; this species tends to be eaten by the common eland, but was spared in this post-fire situation (possibly https://www.inaturalist.org/taxa/119243-Nemesia-affinis) <0.5%
• Hermannia sp., forb-like, already in flower <0.5%Arctotheca prostrata? <0.5%
• Zaluzianskia sp. already in flower (probably either https://www.inaturalist.org/taxa/560266-Zaluzianskya-villosa or https://www.inaturalist.org/taxa/119500-Zaluzianskya-capensis) <0.5%
• Trachyandra divaricata already in flower (https://www.inaturalist.org/taxa/527469Trachyandra-divaricata) <0.5%
• Asparagus sp. <0.5%
• ?Clutia sp. (small leaves, regenerating vegetatively, 10 cm high, and already in flower) <0.5%
• Colchicum eucomoides not yet in flower (https://www.inaturalist.org/taxa/582539-Colchicum-eucomoides) <0.5%
• broad-leafed grasses <0.5%
• wiry tussock-grass already in flower, occurring in small patches <0.5%
• Oxalis with tiny prostrate leaves <0.5%
• Lachenalia sp. post-flowering already <0.5%
• Scabiosa sp. vigorous and green, already in flower, but only a few individuals left owing to ostensible persecution by the common eland (https://www.inaturalist.org/observations?place_id=48632&taxon_id=72344&view=species) <0.5%
• Brunsvigia orientalis (https://www.inaturalist.org/taxa/132796-Brunsvigia-orientalis) <0.5%
• Other unidentified spp., collectively 2%

I noted the absence of the following: Colpoon compressum, any species of Erica or Passerina or Salvia, and Cassytha ciliolata.

In a clump of burnt shrubs, I noted the dead foliage of Chironia baccifera (https://www.inaturalist.org/taxa/426224-Chironia-baccifera). The plant had been scorched to death without being burnt, and remained intact. This endozoochorous species had perished in the fire, but had not regenerated in the post-fire flush. I infer that its regeneration would be both germinative and tardy, dependent on seeds being freshly sown by the angulated tortoise. Val Deverson told me that she had observed many individuals of Chersina angulata (https://www.inaturalist.org/taxa/40021-Chersina-angulata) scorched to death, after the fire.

I summarised the composition of the regenerating vegetation, according to categories, as follows (once again, the values are percent foliage cover):

• graminoids about 20%
• shrubs about 10%
• geophytes at least 5%
• forbs about 2%
• annuals about 1%
• others about 2%.

Val Deverson told me that the first species to appear had been Asparagus sp. (growth form almost ericoid-like, with extremely small leaflets; possibly https://www.inaturalist.org/taxa/580633-Asparagus-capensis). This appeared within two weeks of the fire, within the same summer. It flowered immediately after the leaves appeared.

The next to appear had been Hermannia sp.

In my own assessment of the composition, I noted that Asparagus was still low (about 10 cm high) and hardly noticeable, 8 months after the fire, This indicated that its early vigor of vegetative regeneration had not been sustained. Had it already fruited by the time of my visit?

Val told me that, during the 3-4 years prior to the fire, Brunsvigia orientalis (https://www.inaturalist.org/taxa/132796-Brunsvigia-orientalis) had not managed to produce any flowers at Fairhill. (The flowering season is in March.) This was because the common eland had persecuted this species, to the point of eating every developing inflorescence, and even eating the ground-hugging leaves.

Now, with a post-fire flush of graminoids available to the common eland, the leaves of this geophyte were common in both unburnt and regenerating vegetation; they had apparently been spared because the ungulate had alternative food.

PARENTAL BEHAVIOUR

Val Deverson told me that an infant had been brought out of hiding, for the first time, at about two weeks old, then being led back to a hiding place by both the mother and the father. This meant the adults walking more than one kilometer, with the mother leading. The infant was third in line, trotting to keep up, and seemingly being encouraged by some sort of signal (perhaps softly vocal) from the adult male individual.

Val told me that, more generally, the father was surprisingly protective of infants.

During my visit, there was a new infant, about two weeks old.

Val Deverson had noticed that, since the inferred time of this birth, the group had continually been short by one adult individual. What seemed to have happened was that the infant was continually attended by a babysitter.

However, the remarkable point was that it was not usually the mother that went missing. At times it was a particular adolescent female that was left behind as babysitter, and at other times it was any one of the adult females.

Val had the impression that the infant was made to lie in hiding in unburnt vegetation, whereas the group grazed in burnt vegetation. This implies a cost to the babysitter in terms of foraging.

My commentary:
I do not know whether the infant was lying in hiding, with its babysitter remaining in its vicinity at a discrete distance. However, I infer that the social structure of the common eland, a species that shows creching behaviour, allows a surrogate to babysit the infant, freeing the mother to forage widely enough to maintain the supply of milk.

DEFENSIVE BEHAVIOUR

Val told me the following w.r.t. aggression/defensiveness in the common eland, a species with a reputation for remarkable docility when habituated or kept captive.

Val was putting out bales of food for the common eland at the usual place (near a provisioning trough), and in the usual way. Suddenly and for no apparent reason, an adult female individual charged at her, from about 10 m away. The charge stopped a few metres away from Val, leaving her unnerved.

On another occasion, the 'runt' male individual, excluded by the dominant male from the group, charged Val when she was giving it food at this same, usual place. She fell under the utility vehicle, and it tried to stab her with its horns, fortunately missing. A partial explanation in this case was that this individual was in a miserable state, in the context of its social ostracism.

On yet another occasion, Val was attacked by the whole group, apparently because of the medium-size domestic dog accompanying her at the time. The dog was about 20 m ahead of Val as they walked near the provisioning trough. The animals charged, not towards the dog but towards Val. In her fright, she picked up a branch and threw it, shouting loudly, which stopped the charge.

My commentary:
The common eland seems to react differently to dog and human when these are encountered separately, approaching the former aggressively/defensively, but retreating from the latter. This dog was probably the stimulus for this collective charge. However, a psychological feature of the common eland is that, in this context of alarm, a distinction is not made between dog and accompanying human, despite the human involved being intimately familiar to these individuals. The fearful mind of the common eland does not easily grasp the distinction of identities. So, it directs its defensivene/aggression reaction towards the human - which is subconsciously taken to be the 'larger of a pair of dogs'.

More recently, Val had acquired a dog belonging to a particularly large-bodied breed. When this was still juvenile and inexperienced, it encountered the group of the common eland, while Val watched. The animals advanced, looking at the dog. When the dog approached them slightly (and possibly playfully), they advanced towards it, leading to retreat by the dog. Ungulate and canine seemed to understand each other's body language.

CLICKING JOINTS

Please see https://www.sciencedirect.com/science/article/pii/S0003347215000378 and https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2596769/ and https://www.google.com.au/search?q=Eland+clicking&sxsrf=APwXEdfyYtbgrRlkrcg-_RQEVqWbePbXag%3A1687373451108&source=hp&ei=i0aTZLnhBKaOseMPgJyo2As&iflsig=AOEireoAAAAAZJNUm7wzDVV6lbNvyil21pb-ZjMMlxSL&ved=0ahUKEwj50p75g9X_AhUmR2wGHQAOCrsQ4dUDCAs&uact=5&oq=Eland+clicking&gs_lcp=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&sclient=gws-wiz#fpstate=ive&vld=cid:e5e03bd4,vid:6gDSI1tiPgw and https://www.smithsonianmag.com/videos/category/wildlife/the-click-of-the-wild-eland-antelope/ and https://www.facebook.com/watch/?v=1065638213486566 and https://www.smithsonianmag.com/videos/the-click-of-the-wild-eland-antelope/ and https://www.nationalgeographic.com/science/article/eland-antelopes-click-their-knees-to-prove-their-dominance.

I was surprised to hear the sound of the male adult individual of the common eland. This was audible to me from more than 100 m away. Indeed, I heard this animal before I saw it.

What I found odd was that the clicking sound was metallic, a clink rather than a click, and like an aluminium pendent tapping against a pole.

It strikes me that the 'tink' of the forelegs of adult males of the common eland, as they walk, is emulated by the sound of Maasai cowbells (https://www.videvo.net/sound-effect/masai-cattle-bells-ta-pe539901/250712/ and https://www.istockphoto.com/photo/maasai-man-with-a-cow-bell-gm1158676850-316588909 and https://www.alamy.com/same-tanzania-4th-june-2019-maasai-woman-with-a-cow-bell-image258583248.html). Could it be that part of the utility of cowbells in Africa is for the individuals of Bos to keep together in dense vegetation, as much as for the herders to keep track of their cattle?

ATTENDANCE BY STARLING

Val Deverson told me that the African pied starling (Lamprotornis bicolor, https://www.inaturalist.org/taxa/517007-Lamprotornis-bicolor) and the European starling (Sturnus vulgaris, https://www.inaturalist.org/taxa/14850-Sturnus-vulgaris) closely attended the common eland at times.

The former had a habit of perching on the nape of the common eland. She observed it flying up from the ground around the legs, picking invertebrates off the body (probably including ticks, with which these individuals tended to be afflicted). There was no reaction, in either case, on the part of the ungulate.

During my visit, I observed this behaviour myself on one occasion.

Val also reported that the population of the African pied starling, a mobile species, varied on her property; during the week before my visit, groups had been noticeable here.

(Also see https://www.alamy.com/pied-starling-spreo-bicolor-singing-on-a-sheeps-back-south-africa-overberg-image255403877.html?imageid=F1E85D25-55F2-4ED2-992E-E2EBFBC082B3&p=851122&pn=1&searchId=6cbf8fef94a7ebf1588dc71caa8e5973&searchtype=0 and https://www.alamy.com/stock-photo-merino-sheep-with-common-starlings-sturnus-vulgaris-on-their-backs-122106818.html?imageid=9F2DAE98-F5BB-4930-99D3-E65AA3E562F7&p=292172&pn=1&searchId=6cbf8fef94a7ebf1588dc71caa8e5973&searchtype=0 and http://www.biodiversityexplorer.info/birds/sturnidae/onychognathus_nabouroup.htm and https://www.alamy.com/starlings-forage-on-and-through-a-young-sheep-image550905054.html?imageid=FCDB52E9-522B-4AC5-8175-E3BCC275A526&p=2101386&pn=1&searchId=6cbf8fef94a7ebf1588dc71caa8e5973&searchtype=0 and https://www.alamy.com/domestic-sheep-ovis-orientalis-aries-starlings-sturnus-vulgaris-on-the-back-of-sheep-schleswig-holstein-germany-image414948731.html?imageid=C37C845C-B74E-4DE4-AF97-BDC70E7AB3DD&p=1416600&pn=1&searchId=6cbf8fef94a7ebf1588dc71caa8e5973&searchtype=0.)

to be continued in https://www.inaturalist.org/journal/milewski/81237-field-notes-from-fairhill-nature-reserve-western-cape-province-south-africa-part-2-the-ostrich-struthio-camelus#...

Posted on June 16, 2023 09:00 AM by milewski