From the desk of Bob Boese


Bob Boese - May 21, 2012

When Aloytious Theriot was a youngster he asked his ninety-four year old uncle how the old man managed to live so young.

"Every day," his uncle said, "you have to start breakfast with an omelette sprinkled liberally with gunpowder. Don't be stingy with it and you will live a long healthy life.

Accordingly, Aloytious had a gunpowder omelet every day until he died at the age of ninety-six. He left behind ten children, twenty-three grandchildren, fifty-one great grandchildren, and an eighty-foot hole where the crematorium used to be.

Bob Boese Keep old panfish
First, a little science; fish can be aged by examining scales or various bones (scale exams leave a live specimen). Hard body parts grow as the fish grows, adding annual rings similar to the rings in trees. Under a microfiche reader, panfish scales look a bit like a blend of a fingerprint and a common seashell. Scales get larger as the fish grows by adding to the outside edge. Because fish are cold-blooded and grow very little during winter, a thicker ring is formed, giving a year mark.  Panfish scales are overlapping and flexible and are made of outer layers of calcium compounds and an inner layer of proteins. Fish growth is variable and depends mainly on food supply and water temperature. Northern panfish will have a significantly different growth pattern than their southern cousins. A typical Deep South panfish growth rate chart shows the following.

Bluegill Length (inches) Standard Weight (lbs) Red ear Length (inches) Standard Weight (lbs)
6 0.2 6 0.1
6.5 0.2 6.5 0.2
0.2  0.3
7.5 0.3 7.5 0.3
8 0.4 8 0.4
8.5 0.4 8.5 0.5
9 0.6 9 0.5
9.5 0.7 9.5 0.6
10 0.9 10 0.7
10.5 1.0 10.5 0.8
11 1.2 11 1.0
11.5 1.4 11.5 1.1
12 1.6 12 1.3
12.5 1.8 12.5 1.4
13 2.1 13 1.6
13.5 2.4 13.5 1.8
14 2.7 14 2.1
14.5 3.0 14.5 2.3
15 3.4 15 2.5
From Alabama Cooperative Extension System []

You may start noticing that precision is missing. For instance, fish below six inches are not shown because there can be so much variation in small fish due to available feed.  Panfish feeding on minnows and insects get a more calorie dense diet than those who eat primarily vegetation and will grow larger and heavier. Scales of mature panfish are less precise for estimating age than scales of younger panfish, probably because there is slower growth after the panfish matures. Consequently, some age measurements are guesstimates, and correlation of age to size is sometimes less than precise. Because the growth in the diameter of a panfish's hard body parts is proportional to the growth in length of the fish, examination of scales reveals not only the age of the fish but also its length at all ages up to the current one. For testing purposes, scales are taken from an area near the lateral line. (Lateral line scales aren't used because they have sensors which obscure the growth rings.) Age evaluation is made using comparative measurement of the same scale by different human observers. An average is then used for the final result. Not exactly precise.

Why should fly fishermen care about this? Because we can help future fish generations. Larger mature fish have better genetic qualities than sneakers and satellites who often steal fertilization of bream beds. While fishermen with good ethics and a consideration of the future will be outnumbered by meat fishermen, a bit of conservation is always a good thing and you can still fill your ice chest. While you're loading up for supper, don't take the biggest fish. Culling smaller fish stimulates productive spawns, and good spawns stimulate growth. Repeat: never take the biggest bluegill. Take the smallest adults. Generally, you want to use nine inches as the cut off. Leave those bigger than nine inches and take nine or below. Size is genetic, and larger bluegills tend to be better spawners, and will protect their territory. That means the resulting gene pool favors producing bigger fish.

Examination of natural water bodies finds (and these are general numbers) that panfish such as bluegill, redear, pumpkinseed, goggleye and green sunfish will comprise about eighty percent of the total population by number and about sixty percent of the fish by weight. Predators such as bass, gar, pike (jackfish) and crappie will make up fifteen percent by number and thirty five percent by weight. The rest are usually catfish or carp.

Is there any instance in which big panfish should be culled? Yes, if there are not enough large predators (bass) in the water body, it will get overcrowded with large bluegill. This is not a common occurrence but when it happens you see lots of large panfish, fewer smaller ones and not many large bass. When bass are overharvested, panfish can become the dominant species. At that point, competition between panfish almost always goes to the larger fish, bass focus on young panfish coming off the nest and small panfish numbers diminish rapidly. Now the problem begins to spiral. Nesting habits may change with fewer nests, fewer eggs in nests, and less small panfish surviving past the first year. The lower end of the food chain will be consumed too soon and the only solution is to reduce numbers of larger panfish. On large public waterbodies this phenomenon is quite rare and very difficult to resolve. On smaller ponds, the problem is more prevalent, is obvious when it happens, and several good larger fish fries, adding new fish and not taking bass may eventually restore the balance.

When to eat old panfish is when it's good for the environment and the fishery. Eating old panfish from a large water body will not usually harm the gene pool. Eating panfish below the nine inch mark should never hurt the fishery and may help.  

And here's a cool tool [] at a site that lets you figure out your catch's weight (for nine species) based on size.

Matilda and Adele Gravier, two tiny elderly sisters, were out riding in a large car. Both women could barely see over the dashboard. As they were cruising along they came to a quiet intersection. The stoplight was red but they just went through. Adele, sitting in the passenger seat, thought to herself "My eyes are going bad. I must have seen wrong. I could swear we just went through a red light."

After a few more minutes they came to another intersection and the light was red again and again they went right though. This time Adele was almost sure that the light had been red but was really concerned about her failing vision. She was getting nervous and decided to pay very close attention to the road and the next intersection to see what was going on.

At the next intersection, sure enough, the light was definitely red and they went right through. She turned to Matilda and said, "Sister! Did you know we just ran through three red lights in a row! You could have killed us!"

Matilda turned to Adele and said, "Oh, am I driving?"

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