The fifth sampling event is complete, and we can now add a further 29 alewife to our total catch for the year so far. In addition to the alewife, we also caught multiple white perch and gizzard shad (both common species seen in our net), as well as a pumpkinseed sunfish and several very large carp (see photo below).
Well known to most freshwater anglers (often as a nuisance), pumpkinseeds (Lepomis gibbosus) are a freshwater species of fish in the sunfish family. They typically live in warm, calm lakes and ponds or in small rivers. They eat a wide varies of insects, as well as small mollusks and crustaceans, worms, and smaller fish. They are active throughout the day, often schooling with more pumpkinseeds and other sunfish such as bluegills.
As an interesting defensive adaptation, pumpkinseeds have evolved a dark spot (eye spot) at the posterior end of their operculum (gill plate). This spot mimics the look of an eye of a larger fish as it is positioned further back on the body. When threatened by a predator, pumpkinseeds will often flare their gills to appear larger.
In yesterday’s post we highlighted some of the results from our fourth, and most recent, sampling event. In today’s post, we will be talking about what we caught in the event prior.
The third sampling event took place from March 29th to April 2nd. No river herring were caught; however, we did catch a number of large common carp (Cyprinus carpio), each weighing around 10 to 11 lbs. Common carp are not native to NJ, or to the United States for that matter. They were first introduced to North American in 1831 by Captain Henry Robinson of New York who brought them over from France. In a little over 50 years, common carp had become established in waterbodies throughout the nation. In New Jersey, common carp are present in almost every lake, pond, river, or stream. They have a long lifespan, living anywhere from 12 to 20 years. They forage on the bottom sediments of waterbodies, using their fleshy barbels to taste for insects and other invertebrates. Yet they are largely non-discriminant eaters, often consuming vegetable matter in addition to insects (NJDEP).
In addition to the common carp, we also caught one mirror carp (Cyprinus carpio carpio). The mirror carp is a variant of the common carp that is differentiated by its irregular, patchy scaling pattern. The difference in scales is the result of variants in two genes.
Another notable catch during the third sampling event was of a chain pickerel (Esox niger). This was our first catch of this species in Wreck Pond.
This morning we completed our fourth sampling event at Wreck Pond. Our sampling data from prior years suggests that the majority of alewife that migrate into Wreck Pond over the course of a spawning season do so in one or more large waves, often occurring in April. This pattern was born out this past weekend, as we caught 36 alewife over the course of two days (25 the first morning and 11 the second morning). It is possible more would have been caught if not for the change in weather. A sharp temperature drop halfway through the sampling event followed by strong winds and rain, may have affected the alewife spawning run as many fish are known to alter their behavior due to changes in light, temperature, or pressure associated with storms.
Despite the harsh conditions, we continued to sample. Only one golden shiner and one white perch were caught the remainder of the event. Golden shiners are a predominately freshwater fish that often prefer the quieter parts of the river. Interestingly, the golden shiner was caught this morning. Rainwater flowing into the watershed last night and this morning creating high freshwater flows may help explain its appearance lower in the watershed.
I want to thank everyone who has volunteered so far, particularly those who came out this last event.
Underneath the Wreck Pond Railroad Bridge, the orange buoy is out of the water. This past Monday (3/19), the Society wrapped up its second Wreck Pond sampling event of the year. Unlike our previous sampling event earlier in the month, no river herring were caught. Further, only a couple fishes were caught throughout the event: five white suckers were caught Saturday morning (3/17), and two white perch were caught Monday morning. We believe it is likely that the harsh March weather impacted fish movement (as I write this, the fourth nor’easter of the month is barreling across the state). Throughout the net set, winds were blowing hard west creating upwelling and lowering inshore water temperatures. Ocean temperatures were in the low 40 degrees Fahrenheit, a temperature not preferable for river herring migration. Further, winds have been creating blow-out tides with little water remaining to support fish movement during low tide underneath the railroad bridge.
Earlier this month, we registered our first detection of a tagged alewife at the new culvert. Fish 548 was caught in the fyke net the morning of March 1st. She was tagged and released, and later detected at the entrance of the culvert 15 minutes before midnight. Her abrupt departure, may be an indication of fallback, in which the stress of capture and tagging resulted in her abandoning her migration.
Keep a lookout for the orange buoy from March 29th to April 2nd when we will be out there sampling once again.
On the evening of February 27th, the Wreck Pond Sampling team, including local volunteers, set the fyke net up under the rail road bridge located just south of the Shore Road rail road crossing and adjacent to the pump station. The next morning, four fish were caught including one grass carp, two white suckers, and one white perch. Although the evening event yielded no catch, this morning on March 1, 2018 (drum roll please), we caught two healthy adult alewife river herring. All involved were elated and we immediately began to process the fish to ensure survivability. Once weighed and measured, the two individuals (one male and one female) were both safely tagged and released upstream.
This is the earliest the Wreck Pond team has caught river herring in their net. The species is typically observed once water temperatures are between 42 to 50 degrees Fahrenheit but ocean temperatures have been hovering around 40 degrees and we did not anticipate seeing any herring yet. At the time of capture, the temperature in the pond was recorded at 47 degrees Fahrenheit (39 degrees offshore). We will continue to monitor offshore buoy readings but it would appear that the herring can and do come into Wreck Pond when it is a bit colder offshore. One helpful hint regarding their potential presence close to shore are plunging Northern Gannets observed out at sea. Even though these birds are most likely feeding on bunker, it does make us wonder if schools of herring are mixed in as well.
With the upcoming Nor'easter expected to hit tonight through Saturday morning, the team is curious to see if more herring show up in the net pushed by the winds and exceptionally high tides associated with such a storm. We hope to brave the storm and continue sampling through Saturday, but if the orange buoy is gone, that means we either headed for higher ground or we lost our gear. See you after the storm! If you have interest in participating in any future sampling events, please contact Zack Royle, firstname.lastname@example.org
While for most, the warm days earlier this week probably brought thoughts of sunny spring days spent at the beach or the park, but for us here at the Littoral Society, the warm days brought thoughts of one thing: river herring. River herring migrate into freshwater to spawn in early spring, with the start of their migration triggered by warming ocean temperatures. In anticipation of the herring run into Wreck Pond, we spent the past week installing antennas in the watershed. These antennas are used to track the movement of river herring previously tagged with passive integrated transponder (PIT) tags. Like a fish EZpass, when a tagged fish swims through or past an antenna, its tag number is registered on a computer along with the date and time. Our tagging work has already provided some interesting information on the alewives spawning in Wreck Pond: data indicate spawning alewives spend about 20-30 days in Wreck Pond, and are most active at night. In addition, two fish (Samantha and Bonnie) have been recorded spawning in Wreck Pond in multiple years.
Next week we will be starting our fish sampling. Using a fyke net, we hope to capture adult river herring migrating into Wreck Pond to spawn. We also record information on all other species we catch. If you have an interest in helping to sample, contact Zack at Zack@littoralsociety.org. Stay tuned the next several weeks for more updates on this year’s monitoring.
Earlier this month we held a luncheon for our citizen scientists to thank them for all the hard work they had done the previous year. During the lunch, Society staff updated the attendees on the status of the Wreck Pond work and how the data collected in the citizen science program is helping to improve our understanding of Wreck Pond and our restoration work. Delicious sandwiches were provided by Bing’s Beach House Deli in Avon. In addition to the bird and site monitoring, we plan to expand the program this year to include plant monitoring and trail cam surveys. If you have interest in becoming a citizen scientist, please contact Julie at Julie@littoralsociety.org.
Winter is upon us, and while our monitoring efforts are done for the year, our work continues at Wreck Pond. Currently, Society staff is completing monitoring reports for the year. These reports document the results of our spring fyke net surveys and PIT tagging, as well as our summer and fall seining surveys. Stay tuned for information on where to access these reports once they are made available.
The Society and US Fish and Wildlife Service (USFWS) are also moving forward on the Old Mill Dam Fish Ladder Project. This project will open up almost another mile of potential spawning habitat for river herring. Scientists from USFWS surveyed the dam last month. This survey information, along with water level information collected by our citizen scientists, will be used to develop a conceptual design for the fish ladder. In the upcoming year we will finalize designs and apply for permits.
We also want to remind you that February 3, 2018 will be our Citizen Science Potluck Luncheon held at the Frederic A. Duggan Memorial Building in Spring Lake from 11am to 2pm. This event is a thank you to all our citizen scientists who have worked hard this past year collecting data in and around Wreck Pond. Get your recipes ready and bring your best food for a fun filled presentation of what your data shows and how it is helping us improve Wreck Pond and the larger watershed. Please RSVP by January 12, 2018. Contact Julie at Julie@littoralsociety.org or call 732-291-0055.
October 13, 2017. Friday the 13th. A most portentous day in a most ominous month. Who knew what awaited Society staff and volunteers as they set out to once again sample Wreck Pond? Was some dark menace looming in the depths of the pond ready to snatch up would be seiners? Were the ghosts of a hundred Atlantic silversides lost in seine nets of past waiting to rise up and enact their revenge? There was only one way to tell. The Wreck Pond faithful steeled themselves against the ill-omen in the air, and waded into the cool pond waters…
…and caught some really interesting fish! As always, we caught an abundance of Atlantic silversides; however, mixed in the bunch (and, if not careful, easily missed because of their similar appearance) were a number of bay anchovies. We also caught stripped killifish, northern kingfish, white mullet, and several large snapper bluefish. Remarkably, we also caught one juvenile weakfish (Cynoscion regalis). This marks our first catch of a weakfish in Wreck Pond since we began sampling three years ago.
Weakfish were once an abundant and popular commercial and recreation fish along the coast of NJ and in the Delaware Bay. Overfishing occurred in the 1970s and 80s and regulations were passed in the 1990s and 2000s to reduce fishing pressure and restore stocks. Unfortunately, the population has yet to rebound to its historic levels due to natural mortality from predation, competition, and changes in the environment. Weakfish are preyed upon by striped bass and spiny dogfish, they compete with Atlantic croaker, and warming waters and reduced prey species such as bay anchovy are all likely contributing to high weakfish mortality.