Pond Boss Forums INTRO Questions & Observations Cormorants and fish in ponds

There's been mention of Cormorants on here a few times, and what they can do to a pond. Here's my observations:

I recently completed a Fyke Net survey on a .8 ac pond. Visibility is 16"-18" due to high nutrient loading and an phytoplankton bloom. This survey was done over a 4 day period. There are LMB, BG, BH, Goldfish, Tilapia and Golden Rainbow Trout in the pond. The trout were stocked in October, the Tilapia are stocked annually to control FA (and do a tremendous job).

Water temps are currently between 79 and 80 degrees, dissolved oxygen is very high - it has a Vertex aeration system in it, plus a surface agitator. Surface O2 levels are over 11 mg/l and at the pond bottom they are in the low 9 mg/l range. The trout, even in the warm water, are still alive and active.

Between 2 and 5 Cormorants have been observed on the pond in the past 30 days on a daily basis. They are chased off when seen on the pond, but they return an hour later. There is also a Great Blue Heron that is a regular visitor to the pond.

The first day of the Fyke Net survey, there were 17 15”-18” Trout, roughly 500 3”-8” BG, 38 4”-9” BH, and 30 5”-7” Goldfish in the net. The amount of fish that were in the net that has signs of escaping from the cormorants was amazing. One trout, 8 BH, 11 Goldfish and between 70 to 80 BG showed signs of being grabbed but escaping. Only one Goldfish and 3 BG showed signs of being hit by the GBH and escaping.

The next 3 days of the Fyke Net survey showed roughly the same percentage of fish being hit but escaping from the cormorants. One 8” BG had its gill flap almost completely ripped off, and a few goldfish and BG were missing eyes.

I was surprised at how many damaged/injured fish are in the pond just from less than ½ dozen cormorants in water that has pretty poor visibility.

What a nightmare. I hope you can get a permit for a more permanent solution.

Scott, were you removing fish after the fyke net survey?

Can you release the fish after a fyke net capture?

Scott - sss

Sunil:

Yes, some fish (the first day's trout catch, all Goldfish and all Bullheads) were removed, but the BG and the rest of the trout were released back into the pond.

TJ, unfortunately, a permit or SSS is not an option for this pond. It's in an incorporated area, and while there aren't houses all the way around the pond, high speed lead would cause a safety problem, not to mention a legal problem because of the town ordanance against discharging a firearm.

There were 8 painted turtles caught in the 4 day survey (released) and 2 relatively large snappers caught as well. The snappers were relocated to a creek.

The pond owners two sons were told to "light 'em up" with their paintball guns whenever they saw them on the pond.

Dispatch BG, rig two 5/0 treble hooks on sides, cast out on heavy test braid and heavy action flippin stick and swim it on surface of the water. Ooops, caught a Water Turkey...bummer - better put him out of his misery with this 5 iron.

Can you add cover? We have GBHs all the time and I wonder if there isn't something you'd recommend.

The cormorants fly as soon as they see a human. I don't know if cover will do much good, there is Sago in the pond, enough to clog an electric trolling motor and visibility typically runs 12" during the summer to around 24" during the winter. Right now it's hovering around 18"

Commorants like to dry out on dead trees on or near the water after they have been for a swim. If there is any dead timber standing next to or in the pond, get rid of it. The pond will be less inviting without a place to dry their wings in the sun.

Thanks for the tip. No dead trees near the pond that I can see. I'm actually pretty suprised that they are on the pond. The pond is relatively small, and in a populated area.

The birds could perch on a rooftop I suppose, but it's be kinda hard to remove a house.........

Actually, it isnt that hard to remove a house...it just can be costly to replace it...especially if it wasnt yours to begin with.

I wonder if a scare crow device would help. Just long enough for them to find a better home. Or a scare cannon. Must be something to discourage them.

Lead works well !! Air gun for in town.

Town ordinance against discharging a firearm and houses nearby.

A scare cannon would probably draw complaints. I know one of my neighbors would complain. He complained about the sound of one of my diaphragm compressors and he's 400 feet away!

ewest, that's a good suggestion. I have 2 that would work, just have to spend some time there doing it. They're quiet too. Cecil, snce a pellet gun isn't a firearm, those laws don't apply.

The client is a terrible shot (he admits it), and his boys are more of a "spray and pray" type. Too much playing with paintball guns where pinpoint accuracy isn't necessary.

I have a Gamo Whisper Silent Cat and discharge in town often without a complaint. Pellets fly at 1200 FPS, not sure if they'd take out a water turkey or not.

TJ- I almost wet myself laughing on the whoops and 5 iron comment!

They will induce a WT to die or leave very quickly.

Check your local laws, inside the city limits of Lincoln Ne it would not be legal to discharge a pellet gun.

Wonder if it's the same for Omaha. Oops. Sorry (not sorry) rabbits.

At 1200 fps they can't catch it or see it and with no noise they can't hear it. Only sound will be the smack of the pellet upside the WT. Never give a greasy bird (WT) a second chance.

Dang, ewest! Brutality rising.....

Mine only fly around 900 fps. But they are accurate enough to smack a WT in the head at 50-60 yds easily. Accurate head shots don't need a lot of energy or speed to be lethal.