Even if you aren't a hardcore birder, chances are you have some hidden love for penguins. These flightless birds have captured our hearts through countless movies, beautiful images and their adorable fluffy young.

Panoramic scenes of their large breeding colonies make penguin populations seem limitless, but the IUCN Red List of Threatened Species lists 11 of the 18 species as Vulnerable or Endangered. Penguins have certain characteristics that make them especially vulnerable to large-scale changes to our oceans and climate: their reproductive lifestyle of laying only one or two eggs, inability to fly and feeding strategies all contribute.

A warming climate will change the acidity, temperature and physical patterns of the ocean. The amount of available sea ice will decrease and the timing of the melting will become less predictable. Most penguin species will be negatively affected by the loss of sea ice, as that is where they breed, molt and retreat to from the water. Several species may benefit, though, due to an increase in their possible range and their use of rocky areas for nesting. Penguins rely on commercially important fish species and krill (pdf), so not only are they threatened by climate change, but their prey are also susceptible to overfishing and warming seas.

Penguins are getting hammered on all fronts. Pablo Garcia Borboroglu, the President of the Global Penguin Society, in an interview with Jeremy Hance of mongabay.com says, "In addition, penguins are among the most conspicuous victims of marine pollution. They are particularly sensitive to petroleum spills because they swim low in the water, surface regularly to breathe, do not fly and are less able to avoid petroleum than other seabirds." With the multitude of threats to penguins and their extreme sensitivity, scientists are keeping a close eye on them for warnings of what’s to come for the ocean.

Today is World Penguin Day, so we encourage you to read 14 fun facts about penguins, maybe watch a clip of some dancing penguins, and to take a moment to think about these seabirds that can serve as a cautionary tale of what’s to come from our changing planet.