Runescape states that sharks can be cooked at level 80.

 

On the main cooking guide page, http://tip.it/runescape/index.php?page=cooking_guide.htm, it states level 76.

 

The cooking levels table, http://tip.it/runescape/index.php?page=cooking_guide_levels.htm, is correct at level 80. The cooking calculator, http://tip.it/runescape/index.php?page=cooking_calc.htm, is also correct, as is the cooking planner, http://tip.it/runescape/index.php?page=cooking_planner.htm.

Thanks for your concern, but our guide is actually correct. If you look at the top of the table, the fishing level is also displayed, and sharks require 76 fishing. The cooking level required is correctly listed at 80. I encourage you to submit any mistakes you may find; we'll appreciate it!

 

~George