Calculating bee numbers

[Illo]

We have had our second colony of bees, originally from a hived swarm, for nearly two months now. they are in a 14x12, and doing swimmingly, occupying 6 with brood, to at least some degree, and a further 2-3 with stores. I'd be interested to know how many bees we actually have, but can't find a sensible way of estimating numbers.

can anyone cast any light - I'm sure there is some kind of algorithm for estimating numbers - couldn't find anything in previous threads, though my search technique may be wanting...

LJ

 

[Hivemaker.]

Shake all the bees out and weigh them,so many per lb.

 

[Illo]

How do you get them to stay in the scale pan?

 

[Hivemaker.]

How do you get them to stay in the scale pan?

You don't,you use a meshed box,same as used for shaking package bees.

Or weigh an empty hive, then shake all the bees into that and weigh it again at night when they have stopped flying.

Make sure they are all sitting though,as any flying one's don't count,plus weigh them before they have eaten....or you will get a false reading.

 

[Nellie]

For a rough estimate, according to the Arizona University, College of Agriculture and Life Sciences:

The number of workers found in a honey bee hive can be estimated using the following information:

About one-third of the worker bee in a hive forage every day. Based on average number of flights per day by a single bee and the amount of time spent foraging, the following formula can be used to calculate the number of bees in a hive:

N = 3 x (f/0.0138)
N = number of bees in the hive
f = number of bees seen leaving the nest in one minute
If Joe observes 35 bees leaving a hive in one minute, how many bees are inside? Round off the answer to the nearest whole number.

Answer: 35/0.0138 = 2,536 bees foraging per day. This is about one-third of the hive, so 2,536 x 3 = 7,608 bees in the hive.

Note: The value 0.0138 is based on average amount of time spent foraging for an average honey bee colony on an average day. This value will actually change considerably with amount of food available, weather conditions, etc.

 

[Hivemaker.]

About one-third of the worker bee in a hive forage every day.

Thats where that bit of imformation goes tits up straight away.

 

[Nellie]

Then change the formula to match your assumptions
0.0138 is also a variable and essentially impossible to calculate in any meaningful sense. At least for us. It's an estimate (guesstimate).

But yes, I don't actually disagree that 1/3 seems low if you're assuming a strong colony.

 

[Hivemaker.]

Then change the formula to match your assumptions

Done that,shake bees.

 

[Nellie]

Actually, while a bee might technically be a forager, is it active? It's a subset of the Travelling Salesman problem I believe.

Go for it, I'll take 1/3 of the bees as active foragers and you can fanny around putting boxes on scales, shaking all the bees out and putting them back again .

I've got some code that'll estimate the number of active foragers for a given hive size (circular reference!) but I can't explain in any meaningful sense the underlying maths, depends whether you trust the algorithms or not.

 

[Hivemaker.]

fanny around putting boxes on scales, shaking all the bees out and putting them back again .

Don't put them back again,add a queen and re hive, or sell,it's a package. Well best to leave a few i suppose...

 

[oliver90owner]

Now let's look at this with a bit of common sense.

Hivemaker is right.

Because, for about 4 months of the year there are no bees in the hive.

None there during the night either, unless you rattle their cage.

Don't count your bees leaving while doing orientation flights You might get the wrong answer.

What answer did you want? Yeah right, we can adjust the constant to give any answer you might dream of?

fanny around putting boxes on scales, shaking all the bees out and putting them back again

Doesn't take long. Disagree with Hivemaker, though. I reckon there are so many bees to the kilogram.

Frankly I would not bother, but if, as an excercise, you wished to do it, this method is at least 'fairly' accurate. Could be done when sugar-rolling to displace varroa mites per eg.

RAB

 

[JohnRoss]

Interesting that if they are flying in the box they count. If you weigh a truck load of chickens and half of them are flying round, it weighs the same as a truck load of chickens where they are all on their feet.

 

[Beeline]

Average honey bee weight is 90-100mg so start counting

BL

 

[Nellie]

I don't see weighing as any more accurate either thinking about it. It's still a guesstimate based on an assumption.

What's the proportion of drones to workers? Laden vs unladen workers? What does a worker carrying pollen weigh and do different types of pollen make any appreciable difference?

if we accept the weight parameters In the post above we've already got a 10% margin of error before weve even started which, in the numbers we're dealing with, is a significant variance.

 

[user 6228]

observe and calculate the occupied area (area of a frame x number of fully occupied sides of frames) divide by the plan area of a bee.

 

[Monsieur Abeille]

At a talk by Kim Flottum to the Lincs BKA earlier on in the year he offered a formula for calculating numbers based on the bee coverage of frames. Afraid I can't remember the figures though.

 

[madasafish]

Get Hedgerow Pete to count them... Easy.

 

[Poly Hive]

Its a pretty academic question really, and the answer makes absolutely no difference to anything at all.

Given that if asked how many bees have you got the answer can be a casual "a few" or if you want to impress then say 30k.

Beyond that it is just a nonsense unless you are selling bees by the pound (5k of BTW)

PH

 

[Artisan]

Here is a link to Dave Cushman's site where it shows how to estimate the number of bees on a frame.

http://www.*****************/bee/beesest.html#


Peter

 

[Artisan]

My first try at posting a link.

Replace the ******* with .*****************

Hope thats OK Admin


Peter