Perseverance of a Swallow

In Bear Valley, flocks of cliff swallows (Petrochelidon pyrrhonota) are dancing across grasslands, expertly catching insects as they swoop and swirl through the summer air. Each parent busily carries their catchings of flies, bees, and beetles to hungry young, who open their yellow mouths wide in hopes of being chosen for a treat. Between feedings, the adults—their bright white forehead patches beaming forward like headlamps—perch on the nests to monitor their surroundings before soaring away to collect more food. 

By spending even just a bit of time observing the busy swallow colonies, it’s easy to notice the immense grit and perseverance innately programmed into their small blue and brown bodies. Since the springtime, the swallows have worked hard to build their colonies and start families; they’ve carried thousands of beakfuls of mud to construct their elaborate tunnel nests, laid speckled eggs and kept them warm through cold Point Reyes nights, and diligently fed hungry nestlings. Their journeys haven’t been without setbacks—some individuals in their colonies perished in the sharp beaks of predatory scrub jays or in the tight tangles of the horse hair lining their nests. Through it all, the cliff swallows are persisting together—separate but as one, spiraling through the air and doing what they know best day by day, moment by moment.

At this time of year, swallow nestlings are fledging. See cliff swallows swooping over the grasslands near the Bear Valley Trailhead; they can be identified by their pointy wings. You might also notice some barn swallows flying around the Seashore; barn swallows have forked tails, while cliff swallows have short, square tails.

Ripe Blackberries

This July and August, a sweet treat is ripe for the picking—wild blackberries! Earlier this year, the plants produced small white flowers, which busy bees, flies, and other insects pollinated. The flowers’ petals fell off, and the centers swelled into green berries. Over time, the berries gradually grew to form “drupelets,” the tiny gem-like sections of the fruits which each contain their own seed. The berries’ hue transitions from green to red to purple…and finally to black. Foragers look for berries that are dull black and slightly soft, which indicates peak ripeness and sweetness. 

At Point Reyes, there are two species of blackberry—the native California blackberry (Rubus ursinus) and the non-native Himalayan blackberry (Rubus armeniacus). The two species look similar, but the California blackberry can be differentiated by its smaller thorns and three leaflets with light yellow-green undersides (as opposed to the Himalayan blackberry which has three to five leaflets and a white underside). 

Check out the National Park Service’s guidelines on the quantity of berries that visitors can collect per day.

No-Sky July and Fogust

If you’re visiting the Point Reyes Headlands in the summertime, it’s likely that you’ll be met with a thick shroud of fog. Point Reyes is the second foggiest place on the North American continent, with an average of 200 foggy days per year. Many of these foggy days take place during July, August, and September.

The California Current flows southward from the Gulf of Alaska, bringing cool ocean waters down the coast of California. At Point Reyes, northwesterly summer winds push away warm surface waters, causing cold, nutrient-rich water from the California Current to move towards the surface (aka coastal upwelling, the reason why California is home to so much biodiversity). As water vapor held in air above the ocean cools down, droplets begin to form into the mysterious fog that wisps through Point Reyes’ sweeping landscapes.

For the perfect atmospheric foggy adventure, head through the Point Reyes Headlands towards the Lighthouse. Looking for a fog-free day? Others can relate; records of explorers in the late 1500s complained of “thicke mists and stynkinge fogges” upon their arrival at the coast. The Inverness Ridge often keeps fog from reaching inland areas of the Seashore, so opt to spend time in interior areas such as Bear Valley.

Burrowing Sand Wasps

This July and August, keep an eye out for a peculiar striped, green–eyed insect—the American sand wasp (Bembix americana). 

Females nest in loose sand during the summer months, using their tiny legs and mandibles to dig small cavities…and often fighting against competing coastal winds. After their excavations are complete, the wasps catch and paralyze a fly, place it in the burrow, and lay an egg on top of it. The larvae feed on this fly as they grow, and the females monitor their nests’ food supply and provide more as needed. This act of “progressive provisioning” is unusual for insects, and more common in the bird world. The larvae get to work spinning a cocoon out of sand and “bee-spit,” and overwinter until they emerge as adults the following year—and the cycle begins anew.

See a video captured by PRNSA staff of a sand wasp in action at Tomales Point! Look at those legs go!

← Photo: Valentina Roumi via iNaturalist

Risso’s Dolphin Movements

Off the coast of Point Reyes, pods of grey dolphins leap into the air and slap their tails and flippers on the water’s surface. Suddenly, they become calmer, taking in breaths through their blowhole, and disappear under the water’s surface in search of a meal. Unlike whales who have distinct migratory patterns, Risso’s dolphins are highly food motivated, and their movement is driven by prey—primarily spawning squid—which they will follow up and down the California coast.

To learn more about these marine mammals’ movements, scientists at UC Santa Cruz, Monterey Bay Aquarium Research Institute, and Southall Environmental Associates applied long-term satellite tags and short-term fine-scale movement, acoustic, and video tags to 15 dolphins. They observed individual dolphins moving along different routes throughout the California coast, and were surprised by both how much and how quickly the dolphins traveled. Several of the dolphins spent time in Monterey Bay where they were tagged, then headed to the Greater Farallones National Marine Sanctuary off the coast of Point Reyes. Others made their way to the coast of Mexico in just about a week!

In addition to providing insight on their movement, these kinds of new video based tags are also enhancing understanding of what, where, and how the dolphins feed.

Risso’s dolphins are typically hidden within the deep waters off the coast of Point Reyes, but have occasionally been spotted from the Point Reyes Lighthouse. Since they do not have a defined migratory pattern and move based on prey availability, the dolphins are found in the offshore waters of Point Reyes year-round. If you’re lucky, you could spot them this July or August!

← Photo: NOAA Fisheries/J. Cotton