Spinal deformities in free-ranging bull sharks,Carcharhinus leucas(Müller and Henle, 1839), from the western South Atlantic Ocean

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“…Only one abnormal individual has been sighted among 213 juveniles at Las Teresitas beach during the years 2014 and 2015 (Escánez et al, 2016). This frequency is similar to that reported for Hemiscyllium ocellatum (Bonnaterre, 1788) (0.58%) (Heupel et al, 1999) but lower than Carcharhinus limbatus (Müller & Henle, 1839) (7.7%) (Moore, 2015), Carcharhinus leucas (Müller & Henle, 1839) (11%) (Afonso et al, 2016) or Carcharias taurus Rafinesque, 1810 specimens from aquaria (35%) . Further research is required to determine the causes of these deformities and their impact at population level within the last stronghold of this endangered shark, the Canary Islands.…”

“…Spinal scoliosis has been reported in diverse shark species, most in pelagic sharks that depend on their swimming abilities to catch prey. Many cases have reported abnormal curvatures in the spinal or caudal fin without causing a negative impact on their depredatory activity (Moore, 2015;Afonso et al, 2016). In the same manner, the deformity described here for S. squatina seems not to significantly affect its hunting capacity, which consists in burying itself to catch its preys by ambush.…”

Bioecology and movements of bull sharks, Carcharhinus leucas , caught in a long-term longline survey off northeastern Brazil

“…The continuous use of inshore habitats by C. leucas throughout its lifecycle increases the species' exposure to potentially harmful impacts resulting from anthropic interference, which is obviously higher in these habitats (Beatley et al, 2002). Indeed, skeletal deformities observed in the caudal fins of bull sharks caught at the Brazilian northeastern region suggest a negative influence posed by anthropogenic impacts in the coastal zone (Afonso et al, 2016).…”

Whales, Water, and Disability. Towards a Blue Cultural Disability Studies

“…12 In their study of "skeletal deformities" in bull sharks, which are most likely caused by environmental stressors, André Afonso et al explain that it has commonly been assumed that "a low rate of observations of these phenomena can be expected because many malformations may translate into early mortality and thus not be detectable in older individuals". 13 Nevertheless, their study of two specimens -"mature, seemingly healthy females" 14 with "conspicuous deformities in their caudal fins", 15 caught off Recife, Brazil within a short period of time suggests that their initial assumptions may not necessarily be correct or accurate. In fact, the research shows that "the abnormalities […] had no obvious effect on shark fitness because both individuals were large-bodied and seemed to have healthy weights", which makes the authors reconsider the standards by which they measured the "severity" of the "deformations".…”