A whale watching company in California recently captured on film the rarely seen activity of a blue whale mother nursing her calf.
The calf was estimated to be between four to six months old and will have been born in warmer waters. At birth they are already around seven metres in length and will consume over 200 litres of milk every day, putting on weight at the rate of nearly 4 kilos every hour! In a few months the calf will be weaned but will not reach maturity for at least another ten years.
Please keep in mind that in the United States, obtaining drone footage of marine mammals for research purposes requires federal permits issued under the Marine Mammal Protection Act as well as the Federal Aviation Association. NOAA has also issued recreational guidelines which recommend a distance of approach of at least 1000 feet http://www.nmfs.noaa.gov/pr/uas.html.