How to best manage mosquitos in summer tubbing season?

[TheDukeAnumber1]

I have some summer tubbing seasons under my belt but I would love to hear from some veterans who have been at it for a while. Adding to the mosquito population is my least favorite aspect of outdoor tubs. So how do you manage mosquitos and what extra steps or intentional choices do you make to keep their numbers low? Whether it be fish, natural or artificial products, plants, structure or otherwise.

[Streetwise]

@TheDukeAnumber1, I expected mosquitos in my Vermont water. My juvenile White Clouds seemed to take care of any larvae.

Edited February 26, 2021 by Streetwise

[Biotope Biologist]

Nematodes are quite often overlooked but are quite effective and only target specific species. 

Aerial predators will also keep the adult population in check. Dragonfly, damselfly, and hummingbirds come to mind.

[Daniel]

@TheDukeAnumber1 I haven't noticed any mosquito larva in my outdoor tubs or ponds that have any fish in them. The females mosquitos seem put off by the presence of fish, or at the very least leave no descendants when they have laid eggs in my pools that have fish in them.

One of the ways I manage mosquitos is to provide attractive places for the female mosquitos to lay eggs.

Fetid grass clipping in 5 gallon buckets will attract female mosquitos from the entire neighborhood. From these hotbeds of mosquito breeding, I transfer the rafts to grow out trays. Once I have raised the larva up, I feed them to my fish and the net result is far fewer adult female mosquitos in my area.

 If all else fails you can always create a gene drive and wipe out all the males.

[Anita]

I find guppies do a good job keeping mosquito populations down. During those those early months before the nights warm up enough to put the guppies out, mosquito dunks containing Bacillus thuringiensis (BT) work quite well. In my experience, BT does not seem to affect guppies, snails, shrimp, ostracods, or amphipods living in my plastic-kiddie-pool pond. The National Pesticide Information Center (NPIC) states BT is safe for non-target insects (insects that do not ingest the bacteria), birds, fish, shrimp, and most invertebrates. BT may be toxic to water fleas (I guess they mean daphnia) and honeybees (I wonder if they are drinking the water?)😎

[Hobbit]

@Anita ohh I didn’t know that about honeybees! I use BT regularly around my yard but I wasn’t sure if it would mess with the beneficial bacteria in a fish pond. Sounds like it’s fine from that angle but if it might not be good for bees... 😕

[Anita]

@Hobbit I would be surprised if BT competes with other bacteria in the yard. ☺️ I seem to recall the toxin is very specific to certain insects, and only if they eat it. According to the NPIC web page, it is just one specific strain of BT that is toxic to honeybees. 

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...the aizawai strain is highly toxic to honeybees. Other strains have minimal toxicity to honeybees.

According to EPA.gov, BT is safe for honeybees.

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9. Is Bti harmful to wildlife including honey bees?

Studies indicate Bti has minimal toxicity to honey bees. Bti produces toxins that specifically affect the larvae of only mosquitoes, black flies and fungus gnats. These toxins do not affect other types of insects including honey bees.

At any rate, the brand I use, "Mosquito Dunks," contains the israelensis strain, so I feel pretty safe using it. For your peace of mind, I suggest reading through both web pages. 🤓

Edited March 1, 2021 by Anita

[Daniel]

As a beekeeper I can unequivocally state guppies are non-toxic to honey bees.😊