>My question relating to the above is why take all these surveys on survival rates when I believe most hobbyists aren’t involved with surveys?


The surveys (BIP & NASS) are both complicated with lots of variation on how the counts are taken but if you look at this map 
( https://bip2.beeinformed.org/loss-map/ ) from BIP you can see that a sample of hobbyists is included.  The question remains is their representation statistically significant. In the NASS survey, which I'm a part of as a sideline beekeeper, they claim to have a more representative sample of all beekeepers.  This is a big elephant to eat and I don't think either survey represents the entire picture and I don't think they even can- it will always be a work in process. 



> NASS performed a stratified randomized sample of farming operations that have honey bee colonies. All migratory commercial operations were sampled, in addition to a representative sample of the small scale beekeepers (less than 5 colonies) that qualify as farms. As BIP does not possess a list of registered beekeepers in the US, we performed a sample of convenience, trying to reach a maximum numbers of beekeepers through different means (bee journals, internet, paper survey) and inviting participants to forward the invitation to their peers. The only requirement to be part of the BIP survey was to have colonies located in (at least) one US state or territory.

The split issue that Charles is discussing is handled differently in the two surveys.

>Another significant difference between surveys is how we calculate losses. NASS asked their respondents specifically how many colonies alive at the beginning of the quarter died. This method generally excludes counting any colonies that were made through splitting which died in the quarter. BIP methods calculate losses indirectly, that is, we calculate how many colonies there should have been at the end of a period if none died, and then consider the difference between the expected number of colonies (those at risk of dying) and how many remained alive. We then use these numbers to calculate the loss rate. This means that splits made during the specific seasons that died in the same season are counted as lost. This difference suggests that BIP and NASS numbers would differ most when beekeepers split the most.

Reference Blog Post: 

Interpreting and Understanding the Differences in Honey Bee Colony Loss Numbers From Different National Surveys.

https://tinyurl.com/ya4wkfpd

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