GREAT WHITE SHARK

The JAWS Monster versus reality....


Under various synonyms (such as Maneater and White Death), the white shark has long been a focus for negative media attention, generated by its sometimes lethal interactions with humans and boats.

As a consequence of this typically exaggerated threat to human safety and an almost legendary 'Big Fish' status, the species is deliberately targeted as a source for sportsfishing, commercial drumline trophy-hunting whereby jaws, teeth and even entire specimens are preserved.

Often, their demise comes about merely as piscine whipping-boys of macho individuals pandering to shark attack paranoia.

All of these activities have greatly increased since the JAWS media phenomenon of the mid-1970's - and not merely to the detriment of of the great white.The targeting of other, less high-profile species of sharks has also become vogue.


Nowhere is the great white abundant enough to sustain long-term directed fisheries, with the majority of annual captures worldwide being made incidentally through commercial fisheries operating longlines, setlines, gillnets, trawls, fish-traps and other gear.


The white shark is ensnared throughout the water column in nearshore fisheries and occurs, albeit much less frequently than other mackerel sharks, in the by-catch of some offshore oceanic pelagic fisheries.

White sharks readily approach boats, scavenge from fishermens nets or longlines and devour hooked fish taken by rod-and-line or swordfish harpoon.

Contrary to game hunter bravado, there is nothing particularly clever in enticing these sharks up to boats. Indeed, this vulnerable propensity towards curiosity often results in either their own accidental entrapment or deliberate killing by fishermen. 

In certain regions the white shark has traditionally been viewed only negatively, as manifesting a costly interference to fisheries by damaging gear and 'stealing' catches.

Overall population estimates are unknown, although a recent regional estimate for the famous Dangerous Reef population (South Australia) is given as 200 individuals.

This rare species is unquestionably vulnerable to directed exploitation such as sportsfisheries and the curio trade.

The overall, long-term impact of these mortalities coupled to those caused through indirect fishery captures or indiscriminate anti-shark beach meshing is possibly far-reaching.

The removal of even a few individuals apparently has very tangible effect at discrete localities.  Habitat degradation (pollution and overfishing) also threatens this species and may largely exclude it from areas, perhaps traditionally utilised for feeding or as nurseries,  where it was historically much more abundant. 

Social and Complex behaviour

Contrary to the lonely JAWS spectre of an idiot eating-machine, the white shark is actually a social animal, exhibiting a raft of complex behaviours. Intraspecific ethology and sociobiology in this species are now receiving dedicated research attention, and are considerably more complex than previously recognised or embodied within the archetypal 'lone killer' image. Field-observations have described pecking-orders at feeding aggregations at carcasses which seem based upon a size-hierarchy (see Pratt et al., 1982), where larger sharks dominate in eating; this has also been seen off South Africa with floating baits, but is complicated by individual motivation. Some of the great white's swimming-modes are interpreted as ensuring avoidance of conspecifics and maintenance of a personal space, such as cautiously-timed 'turn-aways' between two animals converging on reciprocal approaching courses. Similarly, the 'parallel-swim' mode is often seen, whereby two sharks heading on the same vector retain an unfluctuating distance from each other, again as what seems to be maintenance of personal space (L.J.V. Compagno, M.A. Marks and I.K. Fergusson; personal obs. and in press). What appears to be a non-injurious means of deflecting competition whilst feeding at the surface has been observed off California and South Africa, whereby white sharks strike or splash conspecifics with the caudal fin in a spectacular exhibition dubbed 'tail-slapping' (Klimley et al., 1996). White sharks will also shove or 'body-slam' other white sharks (and boats) by lateral movements of their bodies, and also use their caudal fins to strike boats and even observers aboard them (M.A. Marks, pers. comm.).

Many white sharks, both adult and immature, have slash and puncture wounds of superficial nature to the head and dorsum, which are inflicted by the teeth of rivals during brief bouts of intraspecific aggression and competition, especially near food resources but very likely also through courtship or other social interactions. In the past, these marks were almost exclusively explained as being caused by the flipper nails or teeth of pinniped prey, but closer inspection and further observation in the field largely excludes this theory. Aggression between these sharks is very inhibited, considering the potential for severe wounding or worse, and includes rather cursory bashing, slashing and grab-release biting with both the upper and lower-jaw teeth. Where elicited on inanimate items offered to white sharks, much of this casual mouthing seems to be investigative rather than any attempt to ingest, and the observer is left with an overwhelming image of the shark using its fearsome jaws with very fine control for tactile sense and manipulation as well as for actual feeding (authors, personal obs.). By the same token, such rather low-intensity biting is typical in attacks on humans, with puncture marks, as opposed to actual flesh removal, being commonplace. Whilst white shark attacks are often explained through a process of 'mistaken identity' with natural prey, underwater observations suggest that the sharks readily distinguish between humans and prey-animals such as pinnipeds. A more compelling hypothesis is that many such 'hit and run' interactions are motivated by interspecific aggression; perceived invasion of personal space, or other motives not directly allied to feeding such as 'play'. As white sharks apparently interact socially by low-intensity biting and grabbing, at least some oral contact with humans and other animals that are not regular prey may have a social framework, with sharks behaving with humans as they would with other sharks. Humans in such interactions may not understand what the shark's body language (including displays such as gaping and hunching) may signify (if they notice them at all) and what responses are appropriate to the context, until the shark proceeds further in the interaction and grabs the person. Work in progress off South Africa suggests that white sharks as individuals and groups confronted by free-swimming skin and SCUBA divers are usually not aggressive even when baits and chum-trails are present but may investigate the divers quite closely without showing any signs of perturbed, agonistic behavior (M. A. Marks, pers. comm.).

White sharks attracted in baited situations exhibit curious behaviours, such as inverted surface-swimming with the mouth agape and gape-displays on the approach to shark cages, divers and so-on, at least some of it being thwart-induced (see Strong, 1996) or displacement behaviour, in a generic sense, as well as int. This activity that is not unlike that observed with the shortfin mako Isurus oxyrinchus. It may appear simply maniacal on films, but such ethology must have a more deep-rooted purpose. In the gape-displays, the palatoquadrate (upper jaw) is exposed for a protracted period during non-feeding, rather akin to a dog snarling and bearing its canine teeth. Indeed, its purpose may be exactly that of the dog - an agonistic threat display that warns-off competitors or intruders of personal space with a display of natural weaponry that requires little further explanation! Some white sharks couple this type of behaviour to a unnaturally stiff swimming mode, with pectoral fins held markedly downwards, and back slightly arched ('hunch' display) and accompanied by periodic gaping that may be directed both intraspecifically (to other white sharks) and interspecifically (for example, to people - but quite possibly, or probably, also to seals, dolphins and other animals). The conspicuous dark axillar blotch (highlighted by bare white axillar skin around it), which is only normally exposed by the 'pecs-down' hunching style of swimming, may play a visual, communicative part in this posturing. Notably, it is a feature of pigmentation found on both white sharks and the shortfin mako (but not the porbeagle or salmon shark) - suggesting that its role, if any, is duplicated or at least overlapping in both species. It's occasional absence as a feature on Mediterranean white sharks may be evidence of a low population density, with very limited intraspecific contact; i.e., the feature has been progressively lost in an adaptorial, evolutionary sense. However, white sharks without axillary spots also occur off South Africa and California where white shark numbers are greater and social contact injuries are commonly seen on sharks. Whilst this explanation remains totally speculative, the apparently low degree of contact between Mediterranean great whites other than for reproduction is further indicated by the dearth of scratches, stabs and other allied marks as seen on the heads and anterior parts of these sharks in regions elsewhere (see above).