Software architect turned photographer Alexander Safanov captured an incredible series of images over several years, documenting the annual sardine run off the coast of South Africa. The images show schools of sardines undulating in beautiful patterns around larger sea creatures like sharks, dolphins and swordfish.
The sardine run occurs from May through July when billions of the newly-spawned little fish move along the east coast of South Africa, creating a feeding frenzy along the coastline. They follow the current of cold water as it heads north up to Mozambique and then pushes out into the Indian Ocean.
Dolphins round up the sardines into ‘bait balls’, which can be up to 65 feet in diameter. Once the sardines are grouped like this, sharks of all varieties move in, as well as birds and game fish like mackerel.
These spectacular shows, which are visible from spotter planes, could be threatened by warming seas. The runs only occur when the water is below a certain temperature; while non-runs used to be rare, they have become increasingly common since 2003.
See more photos at Safanov’s Flickr.