Virginia Institute of Marine Science
Project Description as Proposed:
The Seaside Bays of Virginia’s Eastern Shore are renowned for their local, regional, and global value to migratory birds and marine life of all kinds. The bays serve as critical nursery areas for numerous finfish, both predator and prey, and essential habitat for shellfish, coastal sharks and sea turtles and has been designated by UNESCO as part of their Biosphere Reserve System, receiving national, natural landmark status by the U. S. Dept. of the Interior. This inlet-influenced, ocean dominated system has very good overall water quality. Despite this pristine status the seaside bays suffered an ecosystem state change in the last century: the loss of the seagrass Zostera in the 1930’s due to a wasting disease and concurrent hurricanes (Orth et al. 2006), resulting in the loss of critical ecosystem services for numerous avian and marine species, most especially the bay scallop, Argopecten irradians. Prior to loss of seagrass beds, the region supported a large population of and valuable fishery for bay scallops. Localized extinction of the bay scallop followed the loss of the seagrass beds.
Eleven years of Zostera marina seed additions conducted in these coastal bay systems where Z. marina had not been reported since 1933 has resulted in a rapid rate of Z. marina expansion beyond the initially seeded plots. This effort has been funded from a consortium of grants but notably Virginia’s Coastal Program followed by the NOAA ARRA program and the VA Recreational License Fund and in collaboration with TNC and UVA’s LTER program. From 1999 through 2010, 37.8 million viable seeds were added to 369 individual plots ranging in size from 0.02 to 5 acres totaling 310 acres in four coastal bays. Subsequent expansion from these initial plots to approximately 1700 hectares of bay bottom populated with Z. marina through 2010 is attributable to seed export from the original plots and subsequent generations of seedlings originating from those exports. Water quality data collected over seven years by spatially-intensive sampling as well as fixed-location continuous monitoring document conditions in all four bays that are adequate to support Z. marina growth. In particular, median chlorophyll levels for the entire sampling period were between 5 and 6 µg/l for each of the bays, and median turbidity levels, while exhibiting seasonal differences, were between 8 and 9 NTU. The recovery of Z. marina initiated in this coastal bay system may be unique in seagrass recovery studies because of how the recovery was initiated (seeds rather than adult plants), how rapidly it occurred (years rather than decades), and the explicit demonstration of how one meadow modulated water clarity and altered sediments as it developed and expanded.
In addition to the seagrass restoration work, the NOAA ARRA funds supported the initial attempts at bay scallop restoration. Early results from the bay scallop work yielded important results on the requirements for large scale bay scallop restoration. This FY 2012 project will build on the FY 2009 and FY2011 support for ongoing seagrass and bays scallop restoration work in 2012 and early 2013.
The seagrass restoration component will follow a series of distinct tasks that have proven to be successful during the last eight years of seagrass restoration, including the monitoring of plant performance and the environmental conditions in the transplanted beds. These tasks encompass: 1. Collection of seeds, 2. Processing and storage of seed material; 3. Distribution of seeds in large one acre plots and establishment of test plots in a new region for possible expansion of restoration areas; 4. Monitoring of seagrass success and expansion from ground level assessments of plant cover and aerial photography; and 5. Monitoring of water quality in the restored areas.
The scallop restoration component of this work will build on the successes of the past three years to increase the numbers of reproducing scallops deployed in the grass beds. During 2009 and 2010 we successfully collected scallop broodstock from NC, spawned them in a quarantine hatchery and reared the offspring through adulthood to produce lines of VA broodstock. From these initial spawns we planted approximately 50,000 scallops in cages in the grass bed in South Bay. In 2011 we used the newly-developed VA broodstock lines to produce 2 cohorts of offspring from which we planted over 30,000 in cages in the grass bed to serve as spawners. Two independent surveys (one with divers and one using a suction sampler) conducted during the fall of 2011 revealed that scallops had successfully recruited to the grass bed, though the total population size estimates from these surveys varied widely. These scallops are almost certainly the offspring of the caged broodstock which we deployed and are a strong indication of early success in this program. During FY12 we propose to continue this project with the specific tasks to include: 1) Conduct crosses between NC and VA broodstocks to reduce inbreeding; 2) Transfer 100’s of thousands of scallops to a nursery facility to grow through the juvenile stage; 3) Plant 10’s of thousands of adult scallops in the seagrass beds; 4) Monitor for the presence of newly recruited scallops throughout the southern coastal bays and in the target seagrass beds; and 5) Maintain broodstocks for the next year’s spawn.
Orth, R. J., M. L. Luckenbach, S. R. Marion, K. A. Moore and D. J. Wilcox. 2006. Seagrass recovery in the Delmarva Coastal Bays, USA. Aquatic Botany 84:26-36.
Robert Orth (Seagrass and Water Quality) and Mark Luckenbach (Scallops); 804.684.7392 (Orth) and 757.787.5834 (Luckenbach), email@example.com and firstname.lastname@example.org
4/1/2013 - 3/31/2014; Project Pending
Final Product Received:
Project Summary Provided by Grantee:
Disclaimer: This project summary provides the federal dollars initially awarded to the grantee. Due to underexpenditure or reprogramming of grant funds, this figure may change. For more information on the allocation of coastal grant funds, please contact Laura McKay, Virginia Coastal Program Manager, at 804.698.4323 or email: Laura.McKay@deq.virginia.gov
A more detailed Scope of Work for this project is available. Please direct your request for a copy to Virginia.Witmer@deq.virginia.gov