Month: June 2016
We have submerged aquatic vegetation growing off of both sides of our dock this year on Antipoison Creek for the first time in decades. This observed growth follows reports from the Virginia Institute of Marine Science (VIMS) that the acreage of submerged aquatic vegetation in 2015 Bay-wide significantly increased. Acting as a source of habitat for marine species, such as juvenile blue crabs (which we’ve also seen a lot of this year), it’s nice to see even a little improvement in SAV acreage in our local waters.
Using information from VIMS and the Chesapeake Bay Program, I think this specific grass is Ruppia maritima, commonly known as widgeon grass. While there are several species of submerged aquatic vegetation in the Chesapeake Bay Watershed, widgeon grass and eelgrass are two of the most commonly found species, since they can tolerate a range of salinities. Widgeon grass, according to the Chesapeake Bay Program, typically grows in the slightly brackish to salty waters in the upper, middle and lower reaches of the mainstem of the Bay, but can also be found in freshwater tributaries.
I tried to take underwater photos but the water was too murky today for anything to turn out. However, I’ve included photos of the grasses from above, and a strand of the grass laid out to see what it looks like up close.
Check out today’s front page article, “There’s Always a Catch,” on Chesapeake blue crabs in the Washington Post. Improvements in Bay water quality this year has had a positive impact on underwater grasses and blue crabs, but what does this mean for the Bay’s watermen? Journalist Steve Hendrix spent a day with a commercial crabber and found out temporary crab abundance doesn’t necessarily result in positive outcomes for our local watermen.
Each year, the University of Maryland Center for Environmental Science, the University of Michigan, and the National Ocean and Atmospheric Association collaborates on models predicting the size of the dead zone that will be found in the main stem of Bay over the summer months. Using USGS data on nutrient and sediment loads entering the Bay from the first half of this year, the models can pretty accurately predict how big this dead zone will be. This year’s prediction: the dead zone will be “slightly smaller-than-average.”
Please see the Chesapeake Bay Program for more information.
This spring we’ve read reports from the Virginia Institute of Marine Science (VIMS) on the recent resurgence of submerged aquatic vegetation in the Bay; we’ve seen the latest survey from VIMS and the Maryland Department of Natural Resources showing that blue crab populations are higher this year than in several years past; and we’ve seen the University of Maryland (UMCES) report on the overall improving water quality in the Bay watershed. We’ve noticed some of these improvements firsthand in Antipoison Creek, on Virginia’s Northern Neck. Gary Greenwood shares his observations below:
We just spent three days at our place in White Stone. The weather was terrific, but better than that, we saw things in and around the water that we haven’t seen in the 10 years we have been visiting.
Walking out our dock on Antipoison Creek we noticed a lot of underwater grasses growing on both sides. I understand from our neighbor who has lived on the creek for decades that there used to be a lot of underwater grasses in the creek, but it has been gone for a long time.
The grasses must be providing good habitat for young crabs. We have seen lots of skate in the shallows near the grass, and further out we see crab pots set by five different watermen, based on the colors of the buoys. We have always had crabs of course, but seldom a population to support this many pots.
We visited Mike next door at his oyster farm (www.windmilloysters.com). He was too busy getting a shipment of 5,000 oysters out the door, but he did give us some baby oysters so we can start the next generation in the cage under our dock. Mike said he is shipping more than 15,000 oysters a week, which is great for him and his small operation.
In addition to being a good business, Mike’s oyster farm, with a couple of million oysters in the creek and out in Little Bay, is probably one of the reasons the underwater grasses are returning. (See the earlier post about recent water quality in the creek and Little Bay.)
In the evenings I have been reading Kate Livie’s very enjoyable book, Chesapeake Oysters, about the oysters in the Bay and the people who have made a living from them. She does a great job recounting the history of the oyster from the 1600’s to the present. I hope to finish it this weekend.
One of our goals each time we visit is to eat local seafood whenever we can. This weekend we enjoyed roast oysters at Merroir across the river in Topping, and local rockfish from our fishmonger, Blue Water Seafood in Kilmarnock.
The efforts to clean up the Bay certainly need to continue. We plan to continue monitoring the water quality and donating our information and other resources where we think we can make a difference. This weekend has given us a little optimism that the things everyone does to help the Bay can make a difference.
The University of Maryland’s Center for Environmental Science (UMCES) recently released their report card on the health of the Chesapeake Bay for 2015. The Bay watershed received a grade of a C, which in comparison to past years, is pretty good. Last year’s grade was a D+; the Bay has not received a grade at or higher than a C since 2002.
The score is calculated by analyzing measurements and factors throughout the different segments of the Bay such as streamflow, fish populations, water clarity, levels of nutrients (total nitrogen and phosphorus), acreage of underwater grasses, types and levels of benthic macroinvertebrates, levels of dissolved oxygen and chlorophyll. Each of the following segments of the Bay receives a grade, and the overall score is an average of these areas (individual grades can be found on page 4 of the report).
The segments of the Bay that were analyzed and scored are:
- Upper Western Shore
- Upper Bay
- Patapsco and Back Rivers
- Lower Western Shore (MD)
- Upper Eastern Shore
- Patuxent River
- Choptank River
- Potomac River
- Lower Eastern Shore (Tangier)
- Rappahannock River
- Mid Bay
- York River
- Lower Bay
- James River
- Elizabeth River
Improvements were found for almost all of the measurements listed above, compared to recent years. Total phosphorus levels in the Bay, however, increased from last year, despite models showing a decrease in phosphorus loadings from tributaries. Further study is needed to explain this.
UMCES points out that only two other years – 2002 and 1992 – had scores as good as 2015. However, 2002 and 1992 were drought years, while 2015 was not. (Drought years are generally good years for water clarity, and nutrient and sediment levels, as there is less runoff entering and polluting the Bay and Bay tributaries). So a question this latest report leaves us with is: Is water quality in the Bay improving? Or is the higher score attributed to other factors, such as the milder water temperatures of last summer?