Hive Disaster - Pesticides

[arco]

We returned home from a nice summer vacation to find a big pile of dead bees under our hive.

:'(

I guess they must have been hit by a pesticide.

We live in Northern California - in the Bay Area (Los Altos).  West Nile is in the news here - I think they must have sprayed for mosquitoes or moths.

A shame.  This is our first year with bees - and they were doing very well.  We have got 1.5 supers of honey ready to harvest. 

I think the hive will come back.

Have you heard of something like this? 

Anything I can do to avoid this in the future??

[MrILoveTheAnts]

So the hive is still alive? just a lot of workers dead?

In the future it's best to close up the entrance so they can't get out for a few days. Hopefully they'll announce when they are spraying.

[arco]

Yes - the hive seems to be alive - I checked inside and there were plenty of live bees - though they did seem a bit disoriented.

I vacuumed up the dead bees - and will see how the hive looks at the end of the day.

[UtahBees]

Check with the california state agriculture and food to see if they can point you in the right direction on whether they did spraying or not, and how it effects honeybees (well, we know now, but how it can effect your honey too) and other plans for spraying.

Here in Utah County of Utah (South of SLC), we have the Japanese Beetle, and they are spraying for that. The beekeeper association was very well informed of the spraying, the possible effects, and all of that before they even started. The local rep also came out, answered questions and came and looked at my hive setup even. Very friendly gal that keeps bees herself.

You ought to find out very soon.

[arco]

OK - at the end of the day - my bees are still dying - still do not look healthy...

Could the pesticide effects still be lingering?  Or should I be thinking about something other than pesticide that could be killing my bees??

[Michael Bush]

>Have you heard of something like this? 

Many times.  I've been hit several times over the years.  It's very sad.

[Casimir]

Sorry about your bees it must be devastating to see so many die. :'( It is also too bad you were on vacation because when they spray they tell people days in advance and it is usually the top story on the news. Good thing you mentioned this because while they have not sprayed in my area, I'm sure it is only a matter of time so I will keep a closer eye on the news.

[Dane Bramage]

I used to live in Burlingame and had clients up and down the 280 (e.g. sandhill rd, etc.,). 

Reported Bay Area Pesticide Use from 1999 to 2003 (in pounds
of active ingredients)
Marin County 349,632
Sonoma County 15,320,916
Napa County 10,388,521
Solano County 7,337,722
Contra Costa County 2,970,945
Alameda County 1,632,484
Santa Clara County 4,123,478
San Mateo County 1,270,711
San Francisco County 97,302
Total 43,491,711

Above quote from this report (pdf), which I believe was compiled prior to the west nile & apple moth.   Eekz!

Uh oh, looks like there's more "mosquito fogging" going on just south of you tonight (in ~ 1 hr!)!

Two areas in San Jose, Campbell and Los Gatos with high levels of West Nile virus activity will be treated with pesticide tonight (8/1) at 11 p.m., according to Santa Clara County vector control.

:-x

Curious as to what the :shock: they are spraying there?  Aha, here it is.  "pyrethrins"  I'm familiar with them (produced by certain species of the chrysanthemum plant) - "highly toxic to bees".

No precautions are necessary. This procedure is approved by the US Environmental Protection Agency, the State of California, and the County of Santa Clara.

:roll:

Best of luck to you!

[DayValleyDahlias]

Pyrethrins are higly toxic to bees?  I know people who think because it is OMRI certified that it is ok to use...I would love some sort of article stating the toxicity to bees so that I may share it with my co-growers...I do not use it at all..

[Dane Bramage]

Pyrethrins are higly toxic to bees?

Yes.

http://extoxnet.orst.edu/pips/pyrethri.htm

Pyrethrin is extremely toxic to aquatic life, such as bluegill and lake trout while it is slightly toxic to bird species, such as mallards. Toxicity increases with higher water temperatures and acidity. Natural pyrethrins are highly fat soluble, but are easily degraded and thus do not accumulate in the body. These compounds are toxic to bees also.Because pyrethrin-I, pyrethrin-II, and allethrin have multiple sites in their structures that can be readily attacked in biological systems, it is unlikely that they will concentrate in the food chain (100).

http://www.nysaes.cornell.edu/pp/resourceguide/mfs/10pyrethrum.php

Pyrethrum is highly toxic to bees. The average lethal dose (LD50) for honeybees was measured at .022 micrograms per bee (Casida and Quistad 1995). Direct hits on honeybees and beneficial wasps are likely to be lethal (Cox 2002).

Need more?  or you could refer to the empirical evidence as experienced by "arco" (thread starter) or even have them conduct their own experiments.

I stay away from pyrethrins/thrums as well.  If I had to do anything near the hives (I haven't) I would try to make neem oil and probiotics (compost guano tea foliar feeding) work.

Cheers,
Dane

[Kathyp]

same stuff that's in flea shampoos/sprays,  horse fly spray, even some garden sprays.  i don't use them either.  they work well on direct contact with insect, but the advertised residual effect is not so good.  + they make me a little sick.

they are among some of the least offensive of the insecticides if you must use something.  under most circumstances, they break down quickly.

[reinbeau]

Geez, they aren't using that around here, and we have a huge West Nile and Eastern Equine Encephalitis problem.  Plymouth County Mosquito Control uses Anvil as the adult mosquito killer.  Why would they use something so toxic to bees?  Seems to me California just isn't a very bee friendly place, given what I've heard about clementines and now mosquitoes.

[amandrea]

I have registered my bee yard with the state department on agriculture (NJ) and I'm on the notify list for spraying. I thought all states had the same basic set up?

[DayValleyDahlias]

Thank you Dane, that was exactly what I was looking for, some people tink if they just spray the foliage that it won't harm the bees...they fail to see that the bees drink the dew on the plants, which would have pesticide in it...etc...sad but true.

[qa33010]

   Well that explains why I get sick everytime I bathe the dogs. 

Since my apiary registration was approved for my yard we have not had a mosquito control vehicle go by and I'm up most of the day and night. 

[Michael Bush]

>I'm up most of the day and night.

You need to sleep sometime...

[Cindi]

qa33010.  What, you are up most of the day and night?  When do you sleep?   ;)  I am up a good part of the night, I sleep about 6 hours and that is good for me too.  It is good that you have not seen the mosquito control dudes rollin' along.  Have a wonderful day, great life, great health.  Cindi