Thursday, April 12, 2012

Fish Tagging

For the past several years I have been trying various pond management strategies on my pond. Today I'd like to talk about an experiment I am trying this year, tagging my Largemouth Bass. Ever since I started trying to manage the pond, mostly to increase growth rates of the largemouth, I have always wanted to tag the bass. With the use of tagging I could monitor growth rates and catch rates to help me determine where my pond stands. Recently I found some tagging equipment that I decided to give a shot, but first I'll give some of the basic information about my pond and talk about some of the other things I've done to it over the years.

The pond is around two thirds of an acre by my best estimates. It sits at the edge of a forest but contains minimal amounts of structure (fallen trees, vegetation, etc.). The bottom is a layer of leafs and the depth maxes out at about 12ft. It has existed since before I was born (23+ years) and most likely has been there for a long time and I assume it is natural. It's fed by a small creek that flows in from the woods when it rains. As far as the fish go, it contains good populations of Largemouth Bass and Bluegill Sunfish and a few stocked Channel Catfish that are now quite large.


Many years ago the pond held some decent size largemouth, today that doesn't seem to be the case. Last year I recorded the length of every largemouth caught. A total of 72 largemouth were caught with an average length of 10.67 inches with the biggest fish being 16.25 inches and weighing 2lbs even. Of the 72 I personally caught 47 and I logged 39.75 hours at the pond putting the catch rate at 1.18 largemouth per hour, nothing amazing but I do fish it during all months of the year.  A few years ago I also did some bluegill surveying and found the average to be around 6.5 inches with the biggest fish around 8.5 - 8.75 inches. By these numbers one would say that the pond is somewhat balanced but balanced is not what I'm looking for. My goal is for the pond to produce trophy size largemouth and it hasn't for many years. It is believed that due to a trespasser taking large amounts of fish from the pond, the once trophy largemouth fishery was upset. This has caused the largemouth and maybe the bluegill to become over populated thus stunting the growth. I have considered trying to thin out the largemouth for a while now, I've just never committed to doing it as I enjoy catch and release fishing but this could be the year where I finally try it. Selective harvest is probably the best option for managing a pond. ODNR has an entire pond management handbook on their website containing details of various selective harvest strategies which can be here http://www.dnr.state.oh.us/wildlife/Home/fishing/pond/managementoptions/tabid/6229/Default.aspx
My biggest problem may very well be my lack of harvest in recent years.

In 2006 I decided to stock the pond with some new species. I purchased 25 3-4 inch Hybrid Striped Bass, 25 9-12 inch Channel Catfish, and 10lbs of fathead minnows. The stocking went well, and we immediately started catching the baby channel on blood bait. The last time we caught one of the channels was in 2010 as we rarely target them and it weighed around 6lbs. Some may be approaching 9lbs this year but its hard to say. They may have reached the maximum size that they can achieve within the current state of the pond. To this day we have never caught any Hybrid Stripers. My best bet is that they all got eaten. If one did survive it would be pretty massive, although I don't think any have survived and also evaded being caught.

A couple years ago I decided I would add some structure to the pond since it was lacking in that department. The idea was that if the largemouth have more places to hide and stalk fish, they will exert less energy feeding and in turn grow faster. Not only that but catch rates would approve as the fish congregate in and around the structure. The primary source used for this structure was tree branches, nothing specific, just whatever we found laying around. We started by just throwing some in at select locations. This may have not been the best of methods as fresh wood floats. In hindsight we should have tied a bunch of branches to a rock or cinder block. Regardless, after the limbs got older they eventually sank forming some submerged snags. We also cut down an entire dead tree that fell in the pond forming the biggest snag in the pond. These new snags have produced many largemouth but its hard to say if the overall catch rates have improved.

Snag created from entire downed tree
Years ago the pond contained cattails but muskrats wiped them all out and today there are none. Cattails also provide structure for fish and this could also be a contributing factor as to why the largemouth growth has been somewhat stunted. To counter this I attempted to return cattails to the pond. I gathered some seeds from another location and released them into the pond but didn't have any luck and none grew. I may re-attempt this effort in the future.

Finally, on to the tagging. There are various types of fish tags. I chose one called a self-piercing clamp tag. This tag is a small non-corrosive metal clamp that you can attach to the fishes operculum (gill cover). One might describe it as piercing a fishes ear. I chose this type for many reasons. The main reason was that I felt they were small and would effect the fish minimally. I bought 100 tags, along with a tool to apply them from Jones Fish Hatcheries. I had done business with Jones before as they were who I bought the fish for my 2006 stocking from. Information on the tagging supplies on their website is rather limited and the price was kind of high for what you get but I went with them anyway. Upon receiving my tags and applicator tool I discovered that there were no instructions so I had to figure things out on my own. Below is a picture of a tag properly placed in the tool.

Tag placed properly in the applicator tool
With tagging supplies In hand I headed to pond to tag my first largemouth. Tagging went well, it was as simple as taking a couple measurements (length and girth), holding the fish in the swimming position, and finally clamping the tag on using the applicator tool. Below picture of my tagging station and a video of the process
Tagging supplies, including tags, tape measure, pen, paper, and applicator tool

So far I've tagged a total of 11 largemouth and haven't caught any of the tagged ones. Sometime later this year I will post an update of my progress.

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