Raymond D. Watts, USGS Fort Collins Science Center, Colorado and Vivian Queija, USGS Pacific Geography Science Center, Seattle used data from Kitsap County and from the Washington State Departments of Natural Resources and Fish and Wildlife to associate indicators of shoreline development with sample points along the shoreline.

By evaluating statistical relationships of these indicators to presence or absence of offshore herring spawn, the scientists hypothesized that shoreline development reduces the probability of observing herring spawn.

“Using geography on an urban-regional scale, we seem a little more like social scientists than natural scientists,” said Queija, the team’s geographer and co-investigator in the study.

USGS scientists collecting samples along transect on the east coast of Liberty Bay just outside Poulsbo city limits

“The pattern of urban development has been parcel density that maximized the amount of people to the shoreline and this disruption has systematically changed the system.”

By statistically testing herring spawn against parcel density, then adding other variables such as shoreline modifications, examining sediment samples and looking at vegetative land cover, incorporating and comparing historical information, these scientists hope to look back in time at changes over the past forty years.

The preliminary findings demonstrated that while shoreline modification may generally suppress spawn, it is likely to affect other species to a greater degree than herring, particularly those species that spawn on the beach rather than in intertidal and subtidal waters.

In this study, parcel density indicators had the highest (negative) correlation with herring spawn. Clearly, the probability of herring spawn diminishes as parcel density increases; indicating that much of the shoreline in this section of Puget Sound is poised for significantly diminished herring spawn probability if development density is increased.

Theresa L Liedtke, the team’s fish biologist, working the shores of Liberty Bay

The USGS relationship with the Puget Sound Partnership is through participation in the Puget Sound Nearshore Ecosystem Restoration Project (PSNERP: www.pugetsoundnearshore.org). The primary USGS role for PSNERP is to provide science in support of restoration and preservation of nearshore ecosystems. Since PSNERP began (2001) it has attracted considerable attention and support from a diverse group of individuals and organizations interested and involved in improving the health of Puget Sound nearshore ecosystems and the biological, cultural, and economic resources they support. The Puget Sound Nearshore Partnership is the name chosen to describe this growing and diverse group that supports the goals of PSNERP, but has goals beyond the scope of the PSNERP.

”While this year the focus has been on forage-fish spawning and beach characteristics, I would like to add that scientists from all four of the USGS Disciplines — Biology, Geography, Geology, and Water — have been contributing to that work,” said Richard S. Dinicola, Ground-Water Specialist, USGS Washington Water Science Center in Tacoma.

”Additional work we have planned for this year will include a graduate student from Stanford University partnering with us to investigate the occurrence of pharmaceutical and personal care products in local waters. Sampling devices for those chemicals were deployed during January at two locations in lower Dogfish Creek,” added Dinicola.

During April and May, USGS scientists will be monitoring wave action and water clarity (turbidity) within a few eelgrass beds outside of Liberty Bay to see if light levels are limiting the growth of the eelgrass and locating and measuring ground-water discharge to Liberty Bay and nearby waters to determine (1) if sand lance and surf smelt spawning is associated with ground-water discharge rates to intertidal beaches, (2) if eelgrass growth is associated with ground-water discharge rates to subtidal areas, and (3) the overall contribution of ground water to Liberty Bay.

The “Biological Resources Discipline” including Theresa L Liedtke, the team’s fish biologist, together with Colin Smith and Lisa Gee of the Columbia River Research Laboratory in Cook, has sampled about 10 km of beach shoreline, from Oyster Plant Park to Point Bolin.

“20 beaches were randomly selected, and at each beach we have collected information like presence/absence of shoreline armoring, shade, beach material (sand, mud, cobble, gravel), presence of large woody debris, condition of the area upland of the beach (roadway, landscaped yard, forested), and sources of freshwater,” explained Liedtke, “then we collected beach material samples to look for forage fish eggs.”

They are currently working through those samples hoping to develop a model that will allow a look at some beach variables (like those listed above) and make a prediction of how likely it is that forage fish will spawn on that beach.

“The model will help us to understand what variables are most linked with spawning, and hopefully that will allow us to protect those aspects. For example, it may show that the presence of shade is tightly linked with forage fish spawning — that would suggest that we need to make sure spawning beaches maintain some shade,” said Liedtke, “Our plan for future years is to continue to sample other locations to make the model more robust.”

The next effort in Liberty Bay will be this summer when all the disciplines will be in the field again, sampling and taking a look at influences on food web dynamics related to urban effects.

“I think it’s important to remind people that USGS just does the science, and that we have no management responsibilities. We won’t be the agency that writes or enforces the rules that may eventually be developed to protect shoreline areas — that’s not our role. We do the research and provide data to the management agencies,” Liedtke concluded..