Litters and Neonates of Whale Shark Rhincodon typus Smith, 1828

 

Photograph Litter size TL embryo* (cm) Mass embryo* (kg) TL fem. (m) M fem. (kg) Capture date Capture location Reference
Female had 16 eggcases in one of her oviducts           1910 Ceylon McCormick and Allen with Young (1963)
Rt_images/SitSp318.jpg   see below see below     see below see below McCormick and Allen with Young (1963)


Garrick (1964)
(download as pdf)

  35 embryo was inside 30x14x9 cm eggcase     29 Jun 1953 Gulf of Mexico, eggcase trawled from 57 m Garrick 1964; Compagno 1984;
Compagno 1984: "In 1953 a large eggcase, 30 cm long, 14 cm wide, and 9 cm thick containing a nearly full-term 35 cm embryo whale shark was collected from the Gulf of Mexico, and the assumption was made that the species is oviparous (Baughman 1955; Garrick 1964; Bass et al. 1975). However, the rarity of 'free-living' whale shark eggs, the extreme thinness and lack of tendrils on the only known case, the considerable yolk and partially developed gill sieve in the only known embryo, and the presence of umbilcal scars on larger free living specimens 55 cm long suggest the whale shark is ovoviviparous."
Taiwan04.JPG 300 42-64,
3 size classes
1 kg for 0.58 cm embryo 10 16000 15 July 1995 Off Tong Ho on east coast of Taiwan Joung et al. 1996 (AES abstract). A recently harpooned pregnant female contained about 300 embryos in the uteri. About 15 of the pups were alive and put into containers with sea water. Only 2 could be kept alive, one in Japan, the other in Taiwan. Sex ratio of 237 embryos was 123:114.
  58.6   ?   Feb 2006 25°02′′N, 64°55′′E, about 10 km offshore of the Ormara headland, on the Balochistan coast, Pakistan Rowat et al. (2007): The 2 neonates had been caught in 2000 in fishing nets off of Ormara, Pakistan. The pup preserved was a 58.6 cm TL male (Fig. 1a). The sharks were captured by gill nets fishing in the top 100 m in an area of more than 200 m depth.
From Rowat & Brooks (2012): The method of reproduction in this species was unclear until 1995, when a pregnant R. typus of 10·6 m TL was landed at Chen-Kung fish market, Taiwan (Joung et al., 1996). This fish had 304 embryos combined from the two uteri; many were in their egg cases and had external yolk sacs, but many were also not in egg cases and without a yolk sac. This proved conclusively that R. typus is aplacental viviparous. Three levels of embryo development were found giving TL classes of 42 – 52, 52 – 58 and 58 – 64 cm; the largest being free of their egg cases, with no external yolk sacs, indicating they were ready to be released. This litter is the largest recorded from any shark species.Currently only 19 R. typus specimens of <1·5 m have been reported (Table I), most of which have been captured in fishing gear. Of note, an embryo of 94 cm LT was reported from India with an external yolk sac attached, indicating that it was not full term (Manojkumar, 2003), while in the Philippines a free swimming neonatal R. typus pup of 46 cm LT was found (Aca & Schmidt, 2011). This latter specimen had a freshly healed vitelline scar on its abdomen, where the yolk sac had been recently adsorbed into the body, indicating that it was a full-term embryo (Duncan & Holland, 2006; Hussey et al., 2010). These two findings suggest that R. typus pups may vary considerably in size at birth, compared to those found in the Taiwanese litter. The scarcity of these pups is a significant barrier to fully understanding the life history of R. typus and research into potential anatomical differences in these neonates may lead to the discovery of their habitat.
"A newborn specimen was found inside the stomch of a blue shark (Prionace glauca; Kukuyev 1996)." Compagno (2001).
Rt_images/WhaleShark2009.jpg ? 46       Mar 2009, URL was dated 9 Mar 2009 Pilar town near Donsol in Sorsogon province, Philippines

http://seawayblog.blogspot.com/2009/03/smallest-whale-shark-ever-found.html

Above URL gave TL = 38 cm but Aca and Schmidt (2011) reported TL = 46 cm.

Photograph Litter size TL embryo* (cm) Mass embryo* (kg) TL fem. (m) M fem. (kg) Capture date Capture location Reference
Created April 2002; revised Jan 2015. Back to previous page
Please send comments or corrections to henry@elasmollet.orgt