Overcast start to the day here in Turangi today with high cloud. No wind as of 9:00am. The Tongariro is clear and fishable.
Todays report is for the new amongst you who are unfamiliar with how to tell a male trout apart from a female trout.
The males ( called Jacks) generally have a hook on their bottom jaw. I have seen males interlocked with their mouths kind of like fighting and I guess the bigger they are the more dominant and strong they will be. The females ( called Hens ) usually don’t have a hook or sometimes if they do, a very small one.
(Above) This is an Adipose fin …. these are found on the back of the fish just in front of the tail. This one was kind of neat as it was really spotty. They are kind of squishy and fleshy and some on a brown trout can get really big. I’m not sure what purpose they serve but it is probably like an ear lobe on us humans …. what’s the point ? Main use … to be clipped by Fisheries Managers to mark trout.
I found the below description on WikiPedia.
The adipose fin is a soft, fleshy fin found on the back behind the dorsal fin and just forward of the caudal fin. It is absent in many fish families, but found in nine of the 31 euteleostean orders (Percopsiformes, Myctophiformes, Aulopiformes, Stomiiformes, Salmoniformes, Osmeriformes, Characiformes, Siluriformes and Argentiniformes). Famous representatives of these orders are salmon, characids and catfish.
The function of the adipose fin is something of a mystery. It is frequently clipped off to mark hatchery-raised fish, though data from 2005 showed that trout with their adipose fin removed have an 8% higher tailbeat frequency. Additional information released in 2011 has suggested that the fin may be vital for the detection of, and response to, stimuli such as touch, sound and changes in pressure. Canadian researchers identified a neural network in the fin, indicating that it likely has a sensory function, but are still not sure exactly what the consequences of removing it are.
A comparative study in 2013 indicates the adipose fin can develop in two different ways. One is the salmoniform-type way, where the adipose fin develops from the larval-fin fold at the same time and in the same direct manner as the other median fins. The other is the characiform-type way, where the adipose fin develops late after the larval-fin fold has diminished and the other median fins have developed. They claim the existence of the characiform-type of development suggests the adipose fin is not “just a larval fin fold remainder” and is inconsistent with the view that the adipose fin lacks function.
Research published in 2014 indicates that the adipose fin has evolved repeatedly in separate lineages.
(Below) I took a photo of this that I saw the other day. Something I am sure many of you can relate too 😉