“All our study species are quite challenging to study for various reasons, mostly because they’re really rare and highly mobile.”One of those “difficult birds” is the critically endangered regent honeyeater. They found that a quarter of the birds sang variations of the traditional honeyeater song. And 12 percent of the birds weren’t singing honeyeater songs at all. [CLIP: Little wattlebird]That could mean bad news for the birds’ future—because males singing those untraditional songs were also less likely to be paired up with a mate, compared to their counterparts who sang the standard tune. [Ross Crates et al., Loss of vocal culture and fitness costs in a critically endangered songbird]Crates says the honeyeaters’ loss of songs equates to a loss of culture.