Saturated Salt Solution for Traps

[Sam Droege]

All

Does anyone have experience using saturated salt solutions in bowl/cup/vane trapping situations?

There is great efficacy in running traps over periods of days and many have been very successful in using food grade propylene glycol as a preservative.  That said, it can be prohibitively expensive when you scale it up (note, it can be less expensive if you buy food grade glycol in 55 gallon drums). Gallon containers now run $30-$40 U.S.   

I know that people have used salt solutions for trapping insects, but I can't recall anyone using them in bee traps (probably Frank Parker, the godfather of bee trapping did...).  It seems to me that using salt solutions would be 

1. Inexpensive

2. Possibly preserve DNA (the literature indicates that this is so)

3. Readily available

4. Recyclable with cleaning back into traps

I would be interested in anyone's experiences and any pros and cons.  Experiences with non-bees would also be informative.

Thanks

sam

Lunar Calendar

The moon is a midwife who delivers a bundle of  salt.

The moon sheds a spring-fed light, white as the limestone in Galena, Illinois.

The moon is a knuckle gashed to the bone.

The moon rescinds its blessing, rests its forehead on a crosier of walrus ivory.

The moon is magnetite, a precipitate of iron and oxygen.

The moon is a June bug larva.

The moon snags the train of its wedding dress in the blackberry brambles.

The moon is the pale-bellied mole: lame, hobbled, all maw.

The moon inhales the sluggish cloy of opium, exhales gypsum dust.

The moon is a geode, a glacial erratic, a sinkhole.

The moon is a window opaque with reflection.

The moon, fluent in every tongue, remains mum.

           - ERIC PANKEY

[Cory Sheffield]

Hi Sam,

I did for my PhD surveys in NS (published in 2013). I would add water, a drop of detergent, and a single water softener tablet to each pan, and left them out continuously, collecting the contents each week and replacing the bowl and water solution. The salt unit was standardized, but I used bowls that were larger than the soufflé ones. Nova Scotia was only hot enough to have these dry out on rare occasions. The downsides were crystals forming on bees that are not washed thoroughly, and non-stainless pins can rust over years.

Cory

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[Sam Droege]

Thanks Cory.

Easy technique!

Sounds like a good soak after collecting might decrease some of the salt problems.  Interesting about the pins, unexpected consequences. Seems like you have never continued to use this technique, any thoughts on that?  Seems like it might work well in vane traps and 12 ounce stadium cups. Any thoughts on changes in attraction to the bees?

Appreciation.

Wilding

you can take the girl out of the wilderness

you can strand her bewilder her for a time

you can even hang her upside down

in your rickety attempt to shake loose

the source of her power but you won’t ever

disentangle the wilding from her

the force of a thousand suns unfurling

and hurling her toward the ground

you won’t be able to erase the traces

of salt lacing her ravenous dreams

oh you can try unwebbing her feet

but the lizard in her will keep sunning

itself as the day is long and at nightfall

will crawl up your walls lurking

at the corners of your vision

goading you on while she thwarts   

your every endeavor abandoning

her tail anything required of her

to keep eluding your capture

            -Shara McCallum

 

[Roulston, T'ai H (thr8z)]

Would a saturated salt solution be a super stimulus for mammals that like salt or does that become too salty for them? I need to address an animal drinking problem this year. We all learned in the news last year that hard liquor would likely not work, especially for racoons. I’m considering dematonium benzoate, as noted in the Handy Bee Manual.

T'ai

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[Jim Bess]

Hi All,

 

Depending on the salts used and their concentration, you may end up attracting bees, esp. males.  I worked on a leafcutter bee monitoring project in northern Michigan back in the stone age and the site was remote, so our "urinal" was a large white cedar nearby.  By mid-summer, when the salts had built up, we had to shoo away many male leafcutter bees (with the big white "mitts", prob. Megachile latimanus given sandy soils) visiting the site and licking the soil for salts.  One day in late summer we arrived to find our "urinal" had been excavated down about a foot and a foot in diameter, likely by some mammal(s) eating salty soil.

 

Robert Lederhouse and J. Mark Scriber (at Michigan State University) and associates have done a bunch of cool work with Tiger Swallowtail butterflies and the effects of salts on sperm production and fecundity.  Many other butterflies have also been found to visit and utilize urea and sodium concentrates.

 

Cheers,

 

Jim Bess

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[Sam Droege]

T'ai

I think animals messing with liguid traps come in two main types.  1. Animals that want to eat or drink what is in the trap. 2. Animals that want to mess with the trap because they can.

Type 2 will probably continue to knock over or spill traps no mater what but type 1 can be detered.  In general I would think that most mammals do not drink salt water so would avoid the traps.  I also saw a fleeting reference in a trapping paper to a salt/bleach solution.  Not sure bleach would work given that I believe it would outgass the chlorine within 24 hours.

Dematonium benzoate is used in some ethylene glycol mixes to discourage animals from drinking.  We had used it in a large forest service pilot, but still had problems with some locations with bears and one spot with rodents chewing the bottom of the cups.

Regarding Jim's salt stories.  Frank Parker told me he used to bottle his pee and spray it on vegetation and in the tropics to collect bees that came to those spots.  It would be interesting to see if salt itself is an attractant.  

In any case we will probably run experiments this summer to look at efficacy.  I would encourage others as well.  Great undergraduate project.

[Lusha Marguerite Tronstad]

Hi everyone:

 

We have done a lot of comparisons between pan traps and vane traps, and so we’d like to add what we have learned here.

 

We like vane traps because you do not need to add any liquid or bait to them! That means fewer supplies to buy (no chemicals) and you can pin the specimens  straight from the trap (no washing, etc in the lab unless it rained). Both of these things save money which can be substantial!

 

We leave our vane traps out for a maximum of 2 days. After 2 days, the specimens can degrade (probably worse in our arid climate). Most importantly, we do not want to over collect. Leaving the traps out for 2 days gives you a good idea of the species there. We did some experiments and the species accumulation curves reach an asymptote at 3-5 days. You can set the traps out for an additional 2 days if desired.

 

Nina and I are writing a manuscript with our results and lessons learned, and we’ll send that around once it is published.

 

Lusha and Nina Crawford

 

Lusha Tronstad, PhD

Lead Invertebrate Zoologist

Wyoming Natural Diversity Database

University of Wyoming

307-766-3115

Lusha Tronstad at WYNDD

WYNDD Invertebrate Zoology Program

Teton Alpine Stream Research

Lusha Tronstad at Research Gate

Lusha Tronstad on Google Scholar

 

 

 

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[Sam Droege]

Looking forward to that paper Lusha.

Also, if you want to maximize the number of species detected it would make sense to use Lusha's results and trim to deployment time to 2 days and then move the trap to a new location, which will have a new set of species that could be detected. 

There still is the interesting pattern that in the west Blue Vane traps appear to capture a much wider set of bees than in the East, where captures of large species predominate.  

The old saw that using several trapping techniques including targeted netting will provide the greatest chance of detecting all the species present.

Fox Song

The yards grow ghosts. Between the limbs and wings,

bleached street-lit things, I'm best at moving on.

Hunt-heavy, gray, slunk overlow like so

much weight got in the way, my shape's the shape

of something missed, flash-pop or empty frame.

Though you could say I've made a game of this,

and though midtrickery it might be true,

when evening lingers in the key of leaving

my senses swoon. A synonym for stay,

I'm always coming back. I chew through traps.

I love whatever doesn't get too close.

          - Caki Wilkinson 

[Lusha Marguerite Tronstad]

I agree Sam! We combine vane traps and target netting whenever possible. We have found that some species are only collect with one of the methods. Additionally, some areas are best for one of the methods (e.g., vane traps work at sites with very few flowers, but netting usually results in few observed bees).

 

Lusha

[tgraves]

On attracting type I critters that mess with salt-based traps:   1. Animals that want to eat or drink what is in the trap. 

The species and degree this is a problem will likely depend on the salts available in the rest of the environment. 

Ungulates could definitely drink saltwater in some areas.

Examples:

 in Glacier National Park, some bighorn sheep travel 40 km multiple times/year to get to a natural salt lick and mountain goats follow people around to get their pee.

Bighorn in Dinosaur National Monument and Grand Canyon do not have the same behavior.

Biogeochemists have told me that in mostly natural systems, this depends on the geology.  

Of course in agricultural systems, this would also depend on the deployment of salt blocks.