In the case of TFS, it is known that they reduce BG biomass but the productivity of the system is improved for LMB.
The studies are very inconsistent on this issue with studies going different directions. Some find increased BG biomass due to less predation on early age BG ....
I can see that but it would be great to understand what conditions are responsible for the differences. I would suspect that when BG biomass is below carrying capacity due to an overweight LMB forage-limited biomass that BG survival is increased. In that case, BG would benefit because LMB eat the TFS preferentially and the BG use of lower trophic levels was underutilized.
On the other hand, when BG are near carrying capacity, TFS compromise the BG food chain by competing with the creatures that BG eat. In that case, BG would have less food available and their biomass and RW suffer as a consequence.
I too suspect that TFS and TP interactions are similar. Even so, in either case, LMB benefit but for BG ... it depends. I would be very suspicious of any study which might claim that the ultimate BG carrying capacity would be increased by the addition of TFS (or TP for that matter). For anyone with an emphasis on BG, these species are very likely problematic.
