Good news for Pedro Point Headlands! The PPH Restoration and Trail Improvement Project received the whole-hearted support of the San Mateo County Planning Commission. In the words of one commissioner, “Kudos to the people with the vision to protect and restore this property!”. We also have permission to proceed with construction from our major funder, the Off-Highway Vehicle Division of CA State Parks. We expect to break ground in late August, but before we do any earth moving, we are busy making sure the plants and animals of the Headlands suffer the least possible disturbance during construction. The Coastal Development Permit has provisions for the protection of plants and vegetation communities, bats, birds, butterflies, frogs, and snakes.

Mission Blue Catapiller

Mission Blue caterpillar on summer lupine, San Bruno Mountain. The leaf shows “bullseye” feeding damage typical of Mission Blue caterpillars.

Timing for special species surveys can be critical. We nearly missed the window for getting the Mission Blue Butterfly survey done in time, but thanks to the vigilance of our biomonitoring consultant, Patrick Kobernus of Coast Ridge Ecology, we know that no Mission Blue butterflies will be disturbed by the PPH Project. For those of you who don’t know, the beautiful Mission Blue butterfly has a crazy lifestyle. The tiny fuzzy caterpillars hatch in the spring and chow down on Lupines, their only food source.

Their favorites are silver lupine (Lupinus albifrons) and summer lupine (Lupinus formosus), but they will also snack on varied-color lupines (Lupinus variicolor) if they’re nearby. The young caterpillars make a hole in the outer covering of the leaf and eat only the tasty interior (mesophyll). When the weather turns dry, around June or July, the caterpillars drop off their host plants and go into diapause, a dormant state, until the rains resume in the Fall or Winter. Then they complete their larval stages, pupate, and around April or May, come out as beautiful Mission Blue butterflies.

Pedro Point Headlands has one of the lupines favored by Mission Blue caterpillars, but the butterflies have never been documented in the immediate area, and the survey this summer again showed their absence.

Don’t be Blue:  Meet Acmon Blue

Acmon Blue

Acmon Blue: First check the dorsal side–if it has any orange, it’s an acmon.

However, PPH is home to many other small butterflies, including the striking Acmon Blue. You can recognize this butterfly by the orange band along the edge of the hind wing. The Acmon Blue is the only blue that has this orange band. The Gray Hairstreak below also has orange, but it is not blue and has orange dots not a band.









Meet a Few Other Winged Friends

Gray Hairstreak

Gray Hairstreak

Echo Blue, also called spring azure:  not it has dash like spots rather than rounded ones.

Echo Blue, also called spring azure.

Other butterflies you might see at the Headlands include the Gray Hairstreak,  the Echo Blue (also called spring azure), and the Silvery Blue.


Silvery Blue: Note it only has one row of rounded spots.

Here are a few tips for telling them apart:
1.  First check the dorsal side (in butterflies, the dorsal surface is visible when the wings are held open).  If it is blue AND has any orange, it’s an Acmon Blue.

2.  If it is gray with two orange spots, it is a Gray Hairstreak. The Gray Hairstreak can be confused with Blue butterflies, but it has an orange dot and tiny tails on it’s hind wings.

3.  When the wings are held closed over the body, if it has dash like spots rather than rounded, it is the Echo Blue

4.  With closed wings, if it has one row of rounded spots, it is the Silvery Blue.


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