Do mother rattlesnakes get more aggressive in the spring when their young feed from them? No, that's not true: Baby snakes don't feed from their mother because they are not mammals. Snakes are reptiles and reptiles do not nurse. Newborn rattlesnakes are born with fangs and feed on lizards, not milk, according to the Encyclopedia Britannica.
The claim appeared in a Facebook post (archived here) on March 15, 2019. It opens:
The month of March is here...March and April is when baby rattlesnakes are nursing in the south.
This is what the post looked like on Facebook at the time of writing:
(Source: Facebook screenshot taken on Mon Apr 4 14:06:37 2022 UTC)
The rest of the post reads, "Baby rattlers and their moms become super aggressive during this time. Please be careful out there during this time."
A reverse image search could not find the original source of the picture. It appears to be a large snake with smaller snakes positioned to look like they're feeding from the larger snake.
According to the National Wildlife Federation, rattlesnakes are venomous reptiles. Reptiles do not nurse their young.
Newborn rattlesnakes are born with functioning fangs and feed off lizards, not milk, according to the Encyclopedia Britannica's page on rattlesnakes.