It turns out that in at least one case, modern anglers do not rely on the real fish at all for their mounted trophies. Apparently, a mounted fish trophy can now be made based entirely on the recollection of the one that got away (or was released). Don't get me wrong, in an era of over fishing and increasing sensitivity to the needless destruction of animal life, this makes perfect sense. Why kill the fish when you can have a replica made and mounted?
For our purposes, the question is whether the plastic "fish blank" that is painted to become the "release mount" is classifiable as an article of plastic in Heading 3926 or in Heading 9705 as a collector's piece of zoological interest. This was tackled (see that?) in HQ H188945 (May 9, 2016).
The importer claimed that the plastic fish mounts are used "in the taxidermy industry" to make replicas of game fish and are akin to taxidermied fish mounts in construction, purpose, and channels of trade.
Customs had previously classified fish mounts in 9705. See HQ 952687 (Apr. 30, 1993). In that case, the mount was used as a base to which actual fish parts were attached. Specifically, the skin, teeth, fins, and tail of a once live fish were attached to the plastic mount. Here, the process completely dispenses with the organic fish parts.
Rather than be zoological specimens, according to Customs, these are mass produced from molds made of fish that have been caught, molded, and released. Further, these are decorative items, not likely to be used in, say, museums for scientific or educational reasons. Consequently, Customs classified the plastic fish release mounts in 3926.40.00 as "Other articles of plastic . . . statuettes and other ornamental articles."
Of course, this also dispenses with potentially troublesome compliance issues such as the Convention on Traffic in Endangered Species and APHIS clearance. It also means I can get a mounting of a purely fictional fish like the shark from Jaws or Dory.