Why head first?

[Dinusaur]

Why do Ospreys eat fish head first? This is an age-old debate, I just want to see if there's any new information out there that may shed some light. Also, with migration over, this might be another way to keep this site active. As the picture below shows, very often we see the male osprey bringing in head-less fish to nest during breeding season or they start from the head when eating it whole (second picture). Some say it is because of the nutritional value, some say it is because they want to ensure that the fish is really dead and so on. We also know that Ospreys rotate fish in flight in order to point the fish-head forward (less drag etc. etc.). So, when they land on a tree they see the head first and that's why they start from there. May be it is as simple as that. But why do they eat part of the fish before brining home the rest - that is also an interesting question. Certainly not to satisfy his own hunger, otherwise he would have eaten more than just a little bit of it (first picture). Your guess is probably as good as mine.

[Rotarran]

Interesting question.  Maybe the Osprey knows that's essentially where the fish itself starts so it goes at it in a sequential order.  Or maybe through evolution / passed down knowledge, the Osprey knows that the fish-head rots first and should consume that before anything else.

[BoboBird]

Interesting question.

Head rots quickly makes sense but there is hardly much time between full consumption of the fish that be it head or tail first does not quite matter. The common belief is that the head is more nutritious and the "hunter" of the family needs all the energy he can get to go out constantly for food for the female and babies in the nests.

Another question : I read somewhere there they will not eat fish lips and have actually observed on osprey tear off and discard them. Cannot find where I saw that. Any info about this?