There's a sign on waterless urinals all over the place that claims it saves "up to" 40000 gallons of water per year. It'd have to be running non-stop 24/7/365 for that to be true. There's an ad that I hear playing on NPR sometimes about a container rail train that gets "up to" 500 miles per gallon. Just keeping the lights on uses more gas than that. These "statistics" don't pass the smell test, and this story feels similar to me.
From my reading, the article barely describes them being eaten at all. The black bear "licking moths off his arms" might reasonably be collecting a few at a time. Where does your interpretation of "one by one" come from?
Can you elaborate on this?
One gallon of diesel = ~41kWh. Assuming 30% conversion efficiency that gives us 14kWh. Assuming a 50mph speed to traverse 500 miles means we need to keep the lights on for 10 hours, giving us a power budget of 1.4kW. I don't know what kind of lights locomotives carry but that seems like an awful lot.
Also average freight train speed is tracked and its consistently less than 25mph:
https://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/pu...
Note however that fuel efficiency is almost always given in mpg per freight ton, in which case the power usage of the lights would be amortized over the considerable mass of the train. >400 mpg per ton is not uncommon on a train.
It occurred to me that elevation change could have huge impact on those calculations. More back of the envelope stuff: a 5k ton train requires 13.6kWh to ascend 1m. If such elevation changes are common that would quickly dwarf small values like the power consumption of lights.
The federal standard for gallons per flush for urinals is 1 (with some older models using 5 times that). If we're assuming, they're accessible 365 days/year, that's 110 flushes/day. Seems a little generous, but it's nowhere near as far off as you're claiming.
See: https://www.csx.com/index.cfm/about-us/the-csx-advantage/fue...
> Trains can move a ton of freight over 470 miles on a single gallon of fuel. [0]
The claim isn't that the whole train goes that distance in a single gallon. Each train can carry thousand to tens of thousands of tons of freight. So the train would need thousands to tens of thousand of gallons to go those 470 miles.
This is CXS's calculation [0]
> Schedule 750, Lines 1+3, Diesel Fuel Consumed (freight + switching) = 487,540,790 gallons
> Schedule 755, Line 110, Revenue Ton-Miles = 229,562,353,000245,212,180,000 RTM
> RTM per gallon = (229,562,353,000 RTM / 487,540,790 gals) = 471 RTM/gal
You might think that CXS's numbers are cherry picked, but this matches closely with the numbers of the US rail road industry as a whole which was 435.88 ton-miles per gallon of fuel [1]. The reason that trains are so efficient is that a relatively low speed train on steel wheels with steel rails minimises friction losses[2]. Once the train gets going it doesn't take much to keep it going.
[0] - https://www.csx.com/index.cfm/about-us/the-csx-advantage/fue...
[1] - http://www.factcheck.org/2008/07/fuel-efficient-freight-trai...
[2] - http://www.ctls.uconn.edu/do-csx-trains-really-move-1-ton-of...
"White made that estimation by watching grizzlies with a scope for up to 14 hours per day, while writing his dissertation on the animals at Montana State University-Bozeman. He also counted how many dead moths he could find in each bear “scat,” or pile of poo, and multiplied that by the number of times these bears defecated."
http://www.newsweek.com/grizzly-bears-can-eat-40000-moths-da...
Seems to imply up to 40k/bear, but doesn't give much more for details.
It mentions moths are about a half a calorie each, so just from the moths a bear can consume 20,000 calories/day.
Sorry for being cheeky but the parent literally just addressed your question.
Neither figure seems particularly compelling here, of its "eaten by bears" it seems way too small if it's "eaten by a [single] bear" it seems too big.
"It is estimated that an ambitious bear may consume in excess of 10,000 moths per day, with some estimates ranging as high as 40,000 moths per day."
"One group of scientists analyzed bear scat and revealed that a foraging grizzly could gobble 40,000 moths in a day."
So, I don't find the stat too far-fetched.