July sees fewer strong northwest wind and upwelling events, leading to less nutrients in coastal waters. This starts a shift in phytoplankton populations away from centric diatoms and toward pennate diatoms and picoplankton. Zooplankton are still active and abundant, and rapidly feed on whatever phytoplankton are available.
The California Current moves closer to shore, occasionally bringing oceanic water and open-ocean animals toward the coast.
Schools of small fishes are still abundant in Monterey Bay, along with juvenile rockfish, market squid, and krill (which have nearly reached adulthood). These smaller animals feed a host of larger animals, some of which migrate northward along the coast, including blue sharks, dolphins, humpback whales, blue whales.
The kelp canopy is typically lush by July, and harbors a diverse community of animals and epiphytes (algae that grow on the kelp). Similarly, the community of algae and animals beneath the kelp forest is at its most lush and diverse. Many types of rockfish settle out of the plankton and begin to feed on the animals on the kelp canopy and holdfasts.
As storms pass north of the Central Coast and the wave climate becomes relatively benign, sand moves toward shore and beaches become wider. However, strong northwest winds sometimes generate wind waves that can cause minor beach erosion, but the muscular swells of winter are but a memory.
Crabs, worms, and many other tide-pool animals continue their summer frenzy of reproductive activity in the tidepools.
By July, the newly hatched young of many seabirds will have left their nests and will be foraging for food in coastal waters, along with their parents. Seabirds that nested up north will start trickling back to the Central Coast by late July.
