Weekly graphs: March 20, 2011

I'm going to post graphs weekly for now. We'll see how it goes

This week's theme: Bees don't like rain, or at least they don't gain weight when its rainy.



Note this graph is actually for 8 days.

I tagged thursday night with 'Maintenance': I was working on some outlets and the computer that is monitoring the scale lost power. When it was fixed, it read flat all night till i kicked it. All was restored come morning. Data seems to be inline with expectations, so i'm calling it the same.

-tmk

A week in.

The scale has been under the hive for a week now, and i thought i'd post a couple of updates:

First, some graphs:
Last 24 hrs:


Last week:


The big spike on tue was due to some imbalance in the scale, possibly caused by settling or something. I think the data before it is usable, but if not the data after certainly is.

Also the scale has some temperature fluctuations and is probably accurate to +/- 1/2 lb. The resolution is much higher, but do to the temperature effects and compensation, between any two points could be up to a lb off.

The daily pattern seems to be:
* bees wake up and get flying around 9am
* hive gains most weight between 11am and 3pm
* weight peaks around 6:30pm
* weight tapers off during the next 6-8 hrs, presumably due to evaporation.

Enjoy.

Ups and downs.. evaporation?

There was much discussion about whether all the weight gained by the hive was nectar, and how much would subsequently be lost by evaporation.

Turns out to be quite a lot.

Nectar is reportedly 80%+ water, whereas honey is typically less than 20% water. So in theory you will lose 6/10ths of the volume before it's honey. I was curious to see how long it would take the bees to evaporate the nectar into honey, and sort of expected it to take place in warmer weather.

Nope. Apparently the night time is the right time for evaporation. At least that's my best guess as to what is happening.

All the bees are in there flapping their wings to keep the brood warm, and it seems they are evaporating at the same time. Hive weight seems to peak around 5:30pm right now, and steadily decreases throughout the night, leveling off around 5am.

[ update, did some math, and by weight the nectar to honey ratio is about 9:4, eg 9 lbs of nectar becomes 4 lbs of honey ]

I think i'll start using the weight at 5am as the reference point for how much was gained that day, since the hour-by-hour haul during the day varies so much, and the evaporation seems to continue through the night.

Oh, you want a graph? of course you do:


The purple line on top is today's readings, pink is yesterday, and the light blue is the day-over-day difference between the two. The day-over-day was offset by +100 to get it to all show up on the same graph.

So the net from yesterday (as tabulated at 5am, after most of the evaporation) was about 1.5lbs, and today remains to be seen, but it looks like it'll be around a pound. It's hard to tell what will happen; the weight peaked earlier today vs yesterday, so i'm hoping they got a head start on the evaporation.. We'll have to wait till 5am to find out.

I think I'll wait till 8am or so ;)

busy bees, either way.

Chubby bees

We have data!



So far, the hive seems to have gained around 2lbs today! Will see how it goes by evening, but it's following the general pattern i expected:

[update! looks like almost 3lbs]

* morning: hive weighs less as foraging bees leave
* 11am-3pm hive gets heavier during peak foraging hours



the little ups and downs are probably artifacts of the imperfect temperature compensation, and its affinity for even numbered values. There's probably a mathy way to fix some of that, but it'll have to be post-processed. Maybe i'll just have to get a real temperature sensor installed.

the way it gets lighter in the morning may just be a compensation artifact, and may indicate that the foraging bees really don't weigh that much.

updated graph: