Valentine's Day Image: A stunning pair of Grebes, engaged in courtship Look who is ready for the Valentine's Day! A pair of Clark's Grebes, belonging to the family of graceful water birds, cheered up Twitter ahead of Valentine's Day tomorrow. A stunning video of a pair of Grebes, engaged in "courtship display", was posted by Animal Planet on the microblogging site. The birds are known for treading rapidly on water with their bodies in a nearly vertical position. The video reminds one that loving and caring are not just limited to humans. On Valentine's Day, take a cue - the Grebes can just fire up your imagination.