The Embryonic Development of the Shortfin Mako
(Isurus oxyrinchus)

Photographs and data of shortfin mako litters with embryo of size from
TL ~ 30 mm embryo (attached to yolk sac and still inside the eggcase, embryo shown in center was removed from eggcase) to
TL ~ 750 mm (no external yolk stomach left).
Size at birth is ~ 700 mm (0.7 m).
(Litter size= number of embryos of litter; TL = total length; fem. = mother; *Number in parenthesis gives number of embryos measured if not all were measured)
Slide show using the same photographs
Photograph Litter size TL embryo* (mm) Mass embryo* (kg) TL fem. (m) M fem. (kg) Capture date Capture location Reference
Io03embryo.jpg 9 26-33   3.09 270 9 Jan 1993 Puerto Rico, USA Mollet et al. 2000 (Download PDF)
18 250-310   ~ 3.05 (10') 334 22 Aug 1978 DeSoto Canyon, FL,USA Branstetter 1981;
Pratt and Castro 1991
25 - 30 361(1)
male		 0.800(1) 3.85 calc. ca. 500 Summer 1903 Strait of Messina, It Sanzo 1912;
Mollet et al. 2002 (Download PDF)
18 ca. 406 (16")   ~ 3.66 (12') 547 02 Mar 1990 Kona, Hawaii

Rizzuto 1996;
Glen Hodson pers. comm.
Io_images/MakoPregnant23_09_08.jpg 13 ca. 400-500 estimate   ~ 2.9 estimate 273 23 Sep 2008 off East Taiwan: brought back to dock of Southern Bay Victor Lin pers. comm.
VL01.jpg 14

ca. 500?
male embryo detail

   ~3.05 (10') 258 15 Jan 2003 Taiwan Victor Lin pers. comm.
VL02.jpg ? ca. 500?   ?, likely mother 253 24 Jan 2003 Taiwan Victor Lin pers. comm.
Io16_embryo.jpg 12 504-540 1.435-2.370 3.25 313 15 Jan 1992 Puerto Rico, USA Mollet et al. 2000 (Download PDF)
Io20_embryo.jpg 9 568-620 2.100-2.800 3.34 284 27 Aug 1997 KwaZulu-Natal, South Africa Mollet et al. 2000 (Download PDF)
10 605(1) ~1.1(10) 2.93 calc. 229 20 Feb 1952 Cat Cay, Bahamas Depperman 1953
MakoPup1.jpg 12 670
(1 male)
700
(1 fem)

2.25
(1 male)
2.50
(1 fem)

 3.00 233 10 Oct 2000 10 km off Syndey, Australia Ricky Chan pers. comm.
D&F2001Mako.JPG 8

672-770
(fresh) 622-727
(thawed)

1.955-3.155 (fresh)
1.750-2.934
(thawed) 		3.175 238 Feb 1999 Hawke Bay, New Zeland Duffy and Francis 2001
11 est. 750(11)       late Jan. 1983 Green Canyon LA, USA S. Branstetter 1995 pers. comm.
6 760-820   2.70   17 Feb 1999 Punta Arena BCS Mexico Carlos Villavicencio pers. comm.
Photograph Litter size TL embryo* (mm) Mass embryo* (kg) TL fem. (m) M fem. (kg) Capture date Capture location Reference
Created May 1995; revised October 2008. Back to previous page
Please send comments or corrections to henry@elasmollet.org