COMMISSION

are used for restoration projects. Every native plant
grown in the greenhouse comes from seed handselected
from within the park, ensuring its suitability
to grow and subsist in the dune environment.
There are many invasive species threatening the
dune ecosystem. They include European beach
grass, Russian wheat grass, ice plant, veldt grass,
and Cape ivy. Invasive species degrade or eliminate
important fore dune and dune scrub habitats needed
Oceano Dunes District greenhouse
by sensitive plant and animal species such as the California least tern, Western snowy
plover, marsh sandwort, beach spectacle pod, and surf thistle. Eradication of these invasive
species is done through herbicide application, hand removal, and prescribed burning.
These methods have helped transform the dunes back to their natural state.
Arroyo Grande Creek Fisheries Survey
Arroyo Grande Creek and its lagoon provide sometimestenuous
sensitive habitat for several species of fish and
other aquatic animals in Oceano Dunes SVRA. These
aquatic species, including the federally listed tidewater
goby (endangered) and steelhead (threatened), frequently
are negatively impacted by water quality and availability.
Tidewater goby
The greatest threat to these species and habitats appear to be local water management
activities, especially excessive local groundwater withdrawal (presumably for agricultural
irrigation) as well as the occasional need for manipulation of the lagoon, sandbar, and
riparian areas pursuant to local flood management priorities.
Environmental scientists monitor the status of the fish and habitat within the several acres
of Arroyo Grande Creek (including lagoon). Fishery surveys are conducted approximately
every two to three months, four to six times per year with the primary purpose of ensuring
that SVRA operation and visitor activities do not have any impacts upon these sensitive
resources. Since 2003, State Parks has compiled a valuable record of the dynamics of both
the estuary and the fish community. As with many water bodies in California, these aquatic
features were plagued by record drought conditions throughout much of 2014 and 2015.
Though waters here became too warm and confined for steelhead in recent years, enough
of the lagoon persisted throughout the drought that tidewater goby and a few other species
remain established. This is in contrast to 2008-2009, when the estuary completely dried up
and resulted in temporary loss of these species.
2017 Program Report 151