Ponds around the world--Holland

Marten Scheffer, a biologist at Wageningen University in the Netherlands, grew up swimming in the clear lowland ponds of his country. In the 1980s, many of these ponds turned turbid. The plants would die, algae would cover the surface, and only bottom-feeding fish remained. The cause — fertilizer runoff from nearby farms — was well known, but even after you stopped the runoff, replanted the lilies and restocked the trout, the ponds would stay dark and scummy.

Mr. Scheffer solved this problem with a key insight: the ponds behaved according to a branch of mathematics called “dynamical systems,” which deals with sudden changes. Once you reach a tipping point, it’s very difficult to return things to how they used to be. It’s easy to roll a boulder off a cliff, for instance, but much harder to roll it back. Once the ponds turned turbid, it wasn’t enough to just replant and restock. You had get them back to their original, clear state.

Science is a graveyard of grand principles that fail in the end to explain the real world. So it is all the more surprising that Mr. Scheffer’s idea worked.

By applying the principles of dynamical systems, Mr. Scheffer was able to figure out that to fix the ponds, he had to remove the fish that thrive in the turbid water. They stir up sediment, which blocks sunlight from plants, and eat the zooplankton that keep the water clear. His program of fixing the Netherlands’ ponds and lakes is legendary in ecology.  Source

Resource management planning for Hawksnest State Park

.
The Department of Conservation and Recreation held a public meeting on December 5 to announce their proposed their Resource Management Plan (RMP). The plan encompasses Nickerson State lands on Cape Cod, including Hawksnest State Park.

At the meeting they indicated they were accepting public feedback expressing concerns, issues or ideas. They gave January 10 as the deadline for comments, but said they would accept comments that came later.

The RMP serves as a guide for potential future actions by the DCR. The guidelines are often used as criteria for grants from other public or private agencies. These guidelines may help organizations like the Harwich Conservation Trust to find grant money to help buy property for conservation purposes. The RMP doesn’t include any funding for recommendations..

Please share your thoughts with the DCR

The channel connecting Black and Hawksnest ponds

.
Black Pond and Hawksnest Pond are very different.  Black Pond is shallow, filled with vegetation, and high in nutrients, while Hawksnest Pond is deep, mostly free of aquatic plants, and nutrient poor. 

Yet Black Pond is about a foot higher than Hawksnest. When water levels are high, a strong current flows from Black to Hawksnest.  This probably imports a lot of nutrients into Hawksnest.

In the 1950s tthrough the 1970s, the two ponds were connected only during very high water.  Even then, I did not notice much flow between them.  High bushes on the isthmus must have filtered any water that did flow from Black Pond.

Looking from Black to Hawksnest.  Grass in the water indicates strong flow.

Planning for the future of DCR lands on the Cape, including Hawksnest

.
There will be a meeting hosted by the Friends of Hawksnest to discuss local input to DCR's planning process:

When

 Wednesday, Dec. 18, at 7:30 pm.

Where

First Parish Church in Brewster, on rte 124 just off of 6A, in the church's barn building, accessible from the parking lot. 

Anyone with an interest in the conservation of Hawksnest is invited.  Please RSVP to Suzanne Ryan, suzeryan01@gmail.com, or 774-208-8627. 

. . . . . . . . . . . . . . . . . . . . . . . . .

Background--the planning process

On Dec. 5, the MA Department of Conservation and Recreation held a public forum to introduce their process for planning for State lands on the Cape and Islands.  Below are John Wittmann's notes from the meeting.  Link to a newspaper story on the meeting.

The meeting was held at the Cape Cod Community College. There were around 20 people in attendance and almost half were employees of the State. There were only a few that were actual public.

The meeting's purpose was to introduce us to the process that will be used to create a Resource Management Plan for the Nickerson Complex.

The Nickerson Complex is the name the State gives to all the land managed by the Department of Conservation and Recreation (DCR). This includes many properties across the Cape and Islands, including Hawksnest State Park.

Photos show the basics of erosion control at Hawksnest

Stormwater carries mud, waste, and nutrients to lakes.  It can get this bad (photo from Madison, WI)

Once in the lakes, nutrients feed the growth of toxic algae.

The debris washed in isn't just some leaves.  At Hawksnest with no port-a-potties and parties of up to 25 people, the waste can get nasty.

Erosion and stormwater are one of the largest sources of nutrients to ponds on Cape Cod.   Stormwater runoff causes the erosion, and also caries nutrient-rich debris to the pond--dog waste, human waste, soil, leaves, and garbage.

Nutrients in turn cause toxic algae blooms, and the growth of aquatic weeds that reduce the quality of swimming and other uses.  Once nutrients get into the lake, they are extremely difficult to eliminate.  The pond is degraded forever.  Alum treatment can improve the lake, but it's expensive and has to be repeated periodically.

Erosion around ponds isn't recognized as a problem, because such erosion is normal for the seacoast.  Most people are familiar with ocean beaches, but the ponds are less visited.  So people think erosion around ponds is normal.  In fact, they probably enjoy the enlarged beaches caused by erosion and trampling of shore vegetation.  But the enlarged beach eventually degrades water quality--the very reason they came to the beach.

Why erosion control is needed at Hawksnest

.
Erosion and stormwater are one of the largest sources of nutrients to ponds on Cape Cod.   Stormwater runoff causes the erosion, and also caries nutrient-rich debris to the pond--dog waste, human waste, soil, leaves, and garbage.

Nutrients in turn cause toxic algae blooms, and the growth of aquatic weeds that reduce the quality of swimming and other uses.  Once nutrients get into the lake, they are extremely difficult to eliminate.  The pond is degraded forever.  Alum treatment can improve the lake, but it's expensive and has to be repeated periodically.

Erosion around ponds isn't recognized as a problem, because such erosion is normal for the seacoast.  Most people are familiar with ocean beaches, but the ponds are less visited.  So people think erosion around ponds is normal.  In fact, they probably enjoy the enlarged beaches caused by erosion and trampling of shore vegetation.  But the enlarged beach eventually degrades water quality--the very reason they came to the beach.

Previous erosion control projects at Hawksnest

Our approach

• Use local materials--like logs and mulch.
• Hand tools rather than heavy equipment--less expensive, less disturbance.
• Mulch all surfaces--looks more natural, prevents erosion, promotes plant growth.
• Watch where the rain goes--work with the rain, not against it.
• Explain what we're doing.
• Be responsive to legitimate needs of users--we're trying to repair rather than close paths to the pond.
• Volunteers must coordinate so they don't work against each othe.r
• All projects are approved by Nickerson State Park's superintendent.
• We strongly discourage improvement of roads into Hawksnest.  Poor roads are the best conservation tool--they limit visitation and other damage to the park.  But we may make some repairs to roads, only to prevent harmful runoff from roads to the pond.

Plan of erosion control projects at Hawksest, near Round Cove Rd parking.