Wednesday, February 10, 2010

Intern Corner: River Herring

This week we have a piece written by a pair of Mass Maritime Academy students who are spending their winter break with us. Cadet Michael Kerrigan is a Junior at the Academy and is fulfilling his co-op requirement here at the Landing. Cadet Holly McLaughlin is a freshman who is volunteering to help us out.

Enjoy...

Many rivers and streams are nurseries to different juvenile fish. The reason for this is because they provide protection from predators and provide ideal spawning grounds. Some of these areas can be strictly salt or fresh water flowing, but some are a mixture of both. These areas are commonly known as estuaries. An estuary is a transition zone from where freshwater flows to seawater. This prevents predators from going up these types of rivers and streams because their bodies can't handle the transition of salinity. These types of rivers are very significant because problems continue to grow along them and affect wildlife, specifically populations of spawning fish such as river herring.

River herring are migratory fish that travel in various amounts known as schools. There are normally two fish species linked together when using the term river herring, Alewife (Alosa psuedoharengus) and Blueback herring (Alosa aestivalis). Alewives can live up to 10 years, grow as large as 36cm, and spawn in early spring when water temperatures are between 60F (16C) and 66F (19C). While blueback herring live up to 8 years, grow up to 40cm, and spawn a little later than Alewives in spring when water temperatures are between 70F (21 C) and 75F (24C) .They are both also anadromous fish, which means they are one of the many types of fish that travel up rivers or streams to spawn and then travel out to sea. Although this process seems fairly simple, in some cases it isn't. River herring face many obstacles between the ocean and their spawning grounds causing a continual decline in population .Most herring return to their natal spawning ground, but due to various human activity, they can not reach their destination. This includes, but is not limited to the water quality of the area, over fishing and bycatches, and loss of habitat. All of these factors can be related to anyone living on or near a river.

There are many contributions that can cause a decline in water quality. Along rivers there are recreational activities, houses, and businesses, which all effect the condition of the water. Among some of the recreational activities are boaters, which can be seen as a contributor to water pollution. A lot of boating activity in an area constitutes a problem as well because the river is faced with constant engine idling, harmful bilge pump outs, and oil or gas spills and leaks. Also, many boaters have small portable toilet systems and do not take the proper measures to go to a pump out station as directed. Instead many pump them directly overboard with no treatment leaving sewerage in the area. Houses along the river can be a cause of sewerage infiltrating the river as well. Many of the houses in the area have septic systems with leaching fields. Leaching field discharge often finds its way to bodies of water. Also, when the river has high tides it can flood septic systems and pull back pollution as the tide retreats. Even with homes that had septic systems that have recently connected to the sewerage line can still pose problems. This is because although the system isn't geting anything put into it the leaching fields are still discharging and the soils around them take time to be flushed out. Also, homes around the river have sediment runoff into it. All runoff is, is when it rains or water is applied to a surface it will find low points normally leading to a river or stream and carry material with and substances with it. With homes this can cause problems because many people apply lawn fertilizer, pesticides, and have fluids leaking out of there cars. All of these substances can eventually make there way through runoff to a stream or river. Some businesses produce water pollution as well because they are allowed to discharge small amounts into rivers causing further contamination. All of these factors contribute to water quality. The fish cannot return in order to spawn if the water is not clean enough.

River herring are an easy species to be targeted as bycatch. This is because they travel in schools that can be made up of large numbers. As they move closer to there spawning grounds they become more confined as the river narrows, making them an easier target for fishermen. Besides just river herring which go upstream to spawn, there is also the Atlantic Herring (Clupea Harengus) which are strictly marine fish which have some restrictions on harvesting but not a total closure to the fishery. This is where most of the bycatch takes place and the fish are taken. River Herring have harvesting bans which restrict fishermen from catching them. River Herring populations have been drastically decreasing. For example, fishery landings have declined from 40,000 tons in the 1950s to less than 3,500 tons in 2005 (FAO, 2007). This is why rather than being a targeted species, they are often bycatch, getting caught in gear such as gillnets and midwater trawls.

In the early 1900's, as industry grew, the more people harvested hydro power off of rivers for convenience in factories. With many of these factories gone, still standing dams are left behind. This interrupts the natural flow of the river as well as the habitat of everything that lives in or around the area. Dams make it impossible for the herring to migrate back to their original spawning grounds. Although some actions have been taken to allow fish to pass, there is still no solution to the problem. Fish ladders are one of the solutions, but they do not solve the problem because fish can be too weak to swim up or locate them. If fish ladders are present and hydro power is being generated, they still pose a threat for many reasons. Herring are a velocity species, which will cause them to swim closer to the turbines. As they get closer to the turbines, they will be in the tail race where over oxidization of the water occurs. The herring may also swim up into the
turbine discharge tube, which will either kill them or lead them to a dead end. Some actions put into place are installing metal screens, so the fish don't have access to these areas, but they are not very reliable.

The obstacles that the river herring population face can be prevented. Many of these problems can be addressed with simple procedures. For instance, in boating aspects, funnels can be used to avoid spillage, safer chemicals can be used when cleaning, and catching bilge water while discharging can be helpful. To address the septic system problems, connecting to the town sewerage would be ideal. When doing any yard work or maintenance be cautious of any harmful chemicals used or put down and also check your cars periodically for leaks or drips that could be going onto the ground. Although the cost is high, dam removal would be an great solution for dams that are nonfunctional. Most obstacles river herring face can be eased and if we all do our part we can help rebuild their population.

Friday, January 29, 2010

Don't be fooled


What a difference a day makes. At this time of year it's more apparent than ever. We've had a stretch of warm weather and although we knew better many of us were thinking spring. But the reality is that water temperatures are down near the 30 mark and it only takes a bit of cold air to freeze us in again.

Tuesday, January 19, 2010

Sand Tiger Sharks.

Our annual meeting will be held on January 24, 2010. One of the featured speakers will be Jeff Kneebone of Division of Marine Fisheries. Jeff will be discussing his current PhD research on Sand Tiger Sharks. To pique your interest and give you a bit of background, I'm reposting a DMF summary of the project. This was was originally prepared by DMF in 2008 and featured on our website....

The sand tiger shark (Carcharias taurus) is a large coastal species that ranges from the Gulf of Maine south to the Gulf of Mexico along the east coast of the United States. They are commonly found in inshore waters ranging from 6 – 600 feet in habitats such as surf zones, shallow bays and estuaries, rocky and coral reefs and near shipwrecks. Sand tigers can be identified by the presence of two large dorsal fins, a large anal fin, large thin teeth, dusky spots along the side of the animal and black coloration at the tips of the fins.


Sand tiger sharks in New England:

Sand tiger sharks are seasonal visitors to New England waters during the warmer months of June – November. In the early to mid 1900’s sand tiger sharks were considered to be one of the most common shark species in New England waters and both commercial and recreational fishermen caught large numbers of individuals as far north as southern Cape Cod Bay. During this time, a directed commercial fishery was established in Nantucket Shoals, however, this fishery was short lived due to rapid depletion of the local stock. Unfortunately, increased fishing pressure on the species along the entire east coast of the United States during the mid – late 1900’s severely depleted sand tiger populations, including those around New England. In 1997 as a precaution to stop fishing mortality, the National Marine Fisheries Service (NMFS) prohibited sand tiger sharks from being targeted and retained in both commercial and recreational fisheries. In 2005, Massachusetts state law also prohibited the targeting and retention of sand tiger sharks in state waters.

During the last few years, an increasing number of juvenile sand tiger sharks are being incidentally caught in Massachusetts coastal waters, particularly along the south shore in Plymouth, Kingston, Duxbury (PKD) Bay. Interestingly, occurrence of sand tiger sharks in this region appears to be a relatively new phenomenon as local fishermen claim they have never seen this species in this region until recent years.

Our Research:

Over the last few years the Massachusetts Shark Research Program (MSRP) has worked with commercial and recreational fishermen in the region to investigate the presence and abundance of sand tiger sharks in Massachusetts state waters. Based on recent catch records, most of the sharks inhabiting the region are young of the year (newborn) individuals. While the lack of large females in Massachusetts precludes the use of Plymouth, Kingston, Duxbury Bay for parturition (birth), it appears as though these coastal waters provide secondary nursery habitat for sand tigers that move north from southeastern pupping grounds. Given their increasing numbers in PKD Bay, this embayment may be the most important secondary nursery area for this species north of Delaware Bay.
At present, the MSRP has a study underway goaled at investigating regional movement, habitat use and the effects of capture of sand tiger sharks inhabiting New England coastal waters. Working in conjunction with local commercial and recreational fishermen, the MSRP is actively tagging sand tiger sharks with acoustic telemetry tags to quantify both regional and large-scale movement patterns and habitat use. Each acoustic tag emits a unique coded signal that can be picked up by a series of underwater receivers (listening stations) located in fixed positions within Plymouth, Kingston, Duxbury Bay and Massachusetts coastal waters. If a shark swims within range of a receiver, the unique signal of its acoustic tag will be logged and stored as a data point on the receiver. Periodically the data logged by the receivers will be downloaded onto a computer and analyzed to generate information on regional movement, habitat use and overall ecology. Fortunately, receiver arrays maintained by other researchers in other regions (i.e. Delaware Bay and North Carolina) are capable of detecting fish tagged in New England waters, allowing for the potential to learn about large-scale movements of these young fish.

Data to date

In September 2008, three sand tigers were tagged with acoustic tags within PKD Bay. In the few weeks during which they remained in the Bay, various receivers logged 2,727 detections and provided some interesting information about habitat utilization. Interestingly, one fish tagged in the Jones River in early September was detected in a receiver array near the entrance to Pamlico Sound (Cape Hatteras, North Carolina) during mid-January.

During the 2009 season, the MSRP will continue tagging sand tiger sharks with acoustic transmitters within PKD Bay. Working in conjunction with the Jones River Environmental Heritage Center, the MSRP also hopes to periodically maintain captive sand tiger sharks in a holding tank located at the Jones River Landing for experimental purposes as well as for public outreach.

If you would like more information about this project or would like to report information about sand tiger shark occurrence in Massachusetts waters, please contact the Massachusetts Shark Research Program at 508-910-6329 or 508-693-4372.

References

Bigelow, H. B. and W. C. Schroeder. 1953. Fishes of the Gulf of Maine. Fishery Bulletin of the
Fish and Wildlife Service. 53:74

Gilmore, R.G., J.W. Dodrill, and P.A. Linley. 1983. Embryonic development of the sand tiger
shark Odontaspis taurus (Rafinesque). Fishery Bulletin 81:201-225.

Skomal, G.B. 2007. Shark nursery areas in the coastal waters of Massachusetts. American
Fisheries Society Symposium 50:17-33.

Saturday, November 28, 2009

Eels

When we talk about the fish in the Jones we often focus on river herring. Those of you who have participated in the fish counts at Elm St are familiar with these flashy fish that shoot up the ladder (in far fewer number than we hope for). But while we watch for these swift swimmers there is another species of fish more subtly moving up the river.

American eels (Anguilla rostrata)are another essential part of the Jones River ecology. Like river herring, american eel populations have recently declined. The same types of threats have impacted both of these species - migration obstacles (dams), over harvesting, water quality, and reduced habitat to name a few. However, so little is known about eels that it has been difficult for scientist to pinpoint population numbers, trends, and impacts.

Both river herring and eels fall into the category of 'diadromous' fish, meaning that they spend part of their life in salt water and part in fresh water. Most of us are familiar with how this relates to river herring, salmon, and other fish that afe born in freshwater, migrate out to sea, then return years later to spawn in the same waters where they were born. These are a subset of the diadromous known as 'anadromous'. Eels fall into the other subset - 'catadromous' fish. Eels are born somewhere out in the Sargasso Sea, a region out in the middle of the North Atlantic. The tiny newborn eels then find their way all the way back to the eastern coast of the Americas. For reasons unknown, they branch off and swim up thousands of different rivers along the coast. They continue to migrate upstream as far as possible until finding good safe habitat to grow. Female eels may spend as much as 40 years in our local streams and lakes growing to up to 5 feet. Then on a dark rainy fall night (when you are least likely to notice) masses of eels slither back down the rivers and head out to the Sargasso to spawn and start it all over again.

This year, JRWA and DMF have begun tracking eels in our watershed. We had some fun wrangling eels over 2 1/2 feet long. We unexpectedly found thousands of eels trying to climb the Wapping Road Dam when the water levels dropped. In 2010 we'll be increasing our efforts to understand local Eel populations. And of course we are working hard to revive the conditions needed for their survival.

Thursday, June 4, 2009

River Safari Part 2

....and that was just the beginning (see Part 1 below). After reemerging at my truck on Grove St we were able to drop the trash we had picked up and shed a few layers. Although, with poison ivy threatening from all angles I decided to stay fairly bundled up. We did a short assessment of the road and railroad culverts then headed to Three Rivers Basin to carry on down the river.

Here we opted for the canoe again. After paddling a short ways up Jones River Brook, we headed back into the main channel and pushed downstream. There are some very nice, secluded stretches of river here with diverging channels and low marsh all around. Eventually though, we came to an impassable wall of thorns. Now it was time to ditch the canoe and head out on foot again. Pine assured that it was "only about 600-ft" to the final culvert we were seeking to inspect. Hmmmm, may need to remeasure that Pine! The terrain in the old cranberry bog is soft, wet, hummocky grass that ranges from knee to head high. In between each small tuft of unstable high grass is mud that threatened to steal the hip waders at each step.

It seemed like many miles and many hours, but mostly it was just the tough terrain. Eventually we reached the final culvert. In the end, we were all pleased to see that although the going is pretty rough for people, there does not appear to be any major impediments to fish passage. As Brad put it "There is a lot of work to be done in here but there is no 'project'". Essentially this means that with some chainsaws, brush cutters, and a few gallons of DEET a team of volunteers could clear this stretch of river without needing heavy equipment, funding, or high paid specialists. Boy scout project anyone?!?

I could keep going with this story, but these pictures should be worth a few thousand words....

Wednesday, May 20, 2009

River Safari Part 1


I think of the South Shore as being a fairly crowded place. Nice...but crowded. But every now and then you find yourself in some pretty wild places. Monday was one of those days. With all of our plans to remove the Wapping Road Dam, the next big question is: so what will fish encounter once they can get up there? It's been along time (at least 85 years) since any anadromous fish swam past Wapping Road. Division of Marine Fisheries (and the rest of us) were very interested in having a first hand look at the condition of the river above the dam. Obstructions, rapid changes in elevation, loss of channel definition, and other factors could have serious impacts on the ability of fish to make it upstream....and the success of our restoration efforts.

So, only one way to find out. The day started out much colder and much rainier than the forecasters predicted. So after suiting up in scavenged raincoats and trash bags we jumped in the canoe to conduct our first headwater spawning habitat assessment of 2009. (Maybe more about these assessments in another post some day).

The lake work was uneventful...and then we headed into the wilds of the Jones River. It was only a matter of minutes before Brad (Brad Chase DMF) and I lost Pine in the jungle. We headed back to the truck thinking she had too. No luck. So we dove back into the woods. After about 15 minutes we started to hear more splashing and breaking branches than what we were doing ourselves. So in knee deep mud we reconnected with Pine. At this point it was clear that we had no intentions of stopping. So they carried on while I went back to leave a truck at our next intersection about 3/4 of a mile downstream. Once parked I decided to head upstream. The choices were:
1) In the river. Fairly clear sailing except that the soft bottom threatened to turn thigh deep water into neck deep at water at any step.
2) Along the bank. somewhat dryer than the first option but much muddier, much thornier, and way more poison ivy.
3) Along a trail about 60yrds away from the river.
Although option #3 was by far the easiest it kind of missed the point. So I opted for a combination of 1 and 2.

With phone, watch, and GPS buried deep in pockets under my coat and waders I had no idea how much time had passed when I finally heard Brad and Pine Picking their way downstream. I stopped and hid quietly behind a tree hoping to scare them as they got closer. Instead, I starting looking around at all the water and woods and spooked myself. I kept thinking "I'm glad I'm not doing this in Alaska". That was right about the time I heard Brad say to Pine "I'm glad I'm not doing this in Florida."



More to come in Part 2

Friday, April 3, 2009

Silver Lake High School in the Cranberry Watershed Preserve

While we are busy with our efforts to remove the dam at Wapping Road we are also working on restoring other portions of the watershed. Our most active site right now is the lower portion of Pine Brook. Pine Brook and the Jones River are both coldwater, groundwater fed streams. Pine Brook contains some of the best potential for aquatic species habitat in the system that could serve as a source of ecological recovery of the Jones. Today, Pine Brook suffers from a number of impairments including reduced flows, a series of small barriers and restrictions, limited stream bank vegetation and cover, and poor water quality. At least eight small barriers exist on Pine Brook (debris dams, culverts, and flow diversions for historic cranberry bogs). The impoundments and channelized brook present poor fish habitat as temperatures are unnaturally high and dissolved oxygen is often quite low. Now that these bogs are no longer active and the land is owned by the town, these structures may be removed to restore natural flow throughout the brook. We are currently working to determine the flows necessary to enhance and maintain the habitat conditions necessary to support native fish fauna. The goal is also to increase the amount of habitat available to the fish and mussels in Pine Brook and Jones River within the range of available flows to enhance the resilience and survival of the species.

'Approximate' location of the Preserve.

One of the best things we have going for us here is that the town owns a huge portion of land that Pine Brook runs through…the Cranberry Watershed Preserve. Because of the public landownership there is a high potential for successful and rapid implementation of restoration plans.

An exciting part of the project is the opportunity to partner with the teachers and students at Silver Lake High School. The Preserve is literally in the backyard of the school and makes for a great outdoor classroom. The school’s horticulture program students are conducting species inventories and water quality testing, while the video program is documenting all of the activities and starting to create short films that will be available on line. We’ll get them posted as soon as they are available. Yesterday we went out and did recon of the site with some of the students and discussed the baseline monitoring needs.