Ashy Storm Petrels

The Pacific coast is home to some of the world’s most unique wildlife. In this region, you can find sea turtles, jaguars, and even spider monkeys—all of which play a crucial role in maintaining the balance in this fragile ecosystem. 

But did you know that the Pacific coast is also home to a fascinating seabird that is steeped in legends and folklore? 

We are talking about the ashy storm petrel (Oceanodroma homochroa). 

You can find this nocturnal bird over the waters that stretch from California down to northern Baja, in Mexico.

In this blog, we explore the habits of the ashy storm petrel and the many stories associated with it. We also delve into why it needs the kind of protection Paso Pacifico is committed to providing endangered species of the region. 

Habits and Features of the Ashy Storm Petrel 

The ashy storm petrel, as its name suggests, is smoky grey in color. They have a slightly forked tail and long, slender wings. 

Let’s look at their other main features: 

Size

The ashy storm petrel is a small bird, about the size of a robin, and it weighs slightly over an ounce. That’s quite tiny, right?

But what’s astounding is that this tiny little bird spends most of its life out on the open seas. And, more importantly, it survives in conditions that can challenge even larger birds.

Feeding habits 

The ashy storm petrel mainly eats plankton, larval fish, and small crustaceans. 

However, unlike some of its relatives, our bird does not hover over the water as it looks for food. Instead, it takes a more efficient and energy-saving approach; it rests on the surface of the water and picks its prey up directly.

Breeding

As we said, the ashy storm petrel prefers to spend its time over the water. But it does return to offshore islands in the Pacific during breeding season. Their breeding grounds are primarily on the South Farallon and Channel Islands. 

These birds don’t dig their own burrows. Instead, they build their nests into natural rock crevices, caves, or even under driftwood. Each pair of ashy storm petrels raises only one chick per season, and both parents share the responsibility of caring for it. 

This slow process, which takes approximately four months, is one of the longest breeding cycles of any seabird.

Lifespan

The ashy storm petrel has one of the longest life spans among seabirds, with most living up to 30-34 years on average. 

What’s even more fascinating is that they typically return to the same mate and even the same burrow, year after year. 

What Does the Storm-Petrel Symbolize?

For those who lived on or near the seas, the storm petrel was a symbol of both danger and survival. If you were a sailor in the 18th or 19th century, sighting a storm petrel meant that a storm was on its way, and that you had better start preparing for rough seas. 

European sailors also nicknamed storm-petrels as “Mother Carey’s Chickens.” 

Mother Carey was the name given to the rough seas, while ‘chickens’ represented the souls of dead sailors. For these sailors, the storm petrel became a symbol of the sea’s power to claim lives. 

There is an interesting fact about their original name, too. It is thought to be rooted in the biblical figure of Saint Peter, who walked on water. Petrels often appear to be doing the same thing when they patter on the ocean surface, searching for their food. 

The ashy storm petrel was not just another bird skimming the waves. It was seen as a messenger from the ocean and the water spirits. Because they flew low over the water and appeared suddenly out of the dark, petrels were also regarded as mysterious and a little otherworldly. This often led to them being thought of as guides or protectors.

Predators and Other Ashy Storm Petrel Threats 

The ashy storm petrel faces challenges from both natural predators as well as man-made pressures. When combined, these factors put significant strain on a species that already breeds slowly and has a small global population.

Let’s look at some of  these threats in detail:

Burrowing owls

These owls are a significant threat to storm petrels on the Farallon islands, especially during the winter months. The burrowing owl normally feeds on non native house mice. These become scarce in cold weather, which leads the owl to start hunting the ashy storm petrel. 

This predation is especially harmful because the owls can take many birds in a short period and weaken entire colonies in the process. 

Human-introduced predators

Rats and feral cats are another major threat. Neither is a native species to these offshore islands. Rats arrived as stowaways on ships, and cats were often bought by people to control rodent populations, or even as pets at lighthouses or military outposts. Over time, their population spread and became feral. 

Because there was no natural check on these creatures, they began raiding seabird colonies. Rats consume eggs and chicks directly from burrows, while cats prey on both young and adult birds. 

And, as the ashy storm petrel only produces one chick per breeding season, even small losses from these predators can have significant consequences.

Other native predators 

Native birds such as gulls and larger seabirds also occasionally prey on storm petrel fledglings that are leaving their nest for the first time. Although this is part of the natural balance, it adds another layer of pressure.

Light pollution 

Fishing boat lights, cargo ship lights, and even lights from coastal developments can disorient the ashy storm petrel. This often results in collisions and leaves the bird unable to return to sea. This further makes them easy prey. 

Other pollution

Petrels can mistake floating plastic fragments in the ocean for prey. When they fill their stomachs with such indigestible material, it can lead to starvation. Even when plastics don’t kill directly, they release harmful chemicals that build up in the birds’ bodies over time.

Climate change

The California Current is a cold-water system that is rich in nutrients. It also fuels the entire marine food chain of the region. However, this crucial system is being threatened by rising sea temperatures. 

As the water gets warmer, it reduces the availability of plankton and small fish, the primary food sources of the ashy storm petrel. When there is less food, the chances of breeding success are also low.  

How You Can Help the Ashy Storm Petel 

There are only about ten thousand ashy storm petrels left in the world today. In fact, the bird has also been classified as endangered by the International Union for Conservation of Nature (IUCN). 

This means that a single oil spill or season of poor food supply can set back entire colonies.

At Paso Pacifico, protecting the ashy storm petrel is an integral part of our larger vision. This involves safeguarding coastal ecosystems and ensuring that wildlife and people can thrive together. Your smallest contributions, whether it’s sharing knowledge, supporting restoration, or helping raise awareness, play a key role in keeping these efforts alive.