May 1 The first day of May, after two days of a good rain, saw the return of the alewives to the passageway after a ten day absence, and in the hundreds! The water level was at a good depth, an increase of at least two inches, so the sandbars of last week were now buried and the fish were making their way in easily (and happily, or so it seemed to my eyes). There was still some spawning activity at the Walker's Pond opening though less than last month which can be attributed to the scouts who generally come and go quickly. The one unfortunate occurrence was the apparent blockage in the culvert pipe. Although some fish, single file, had gotten through in April, before the water level became too shallow, this time none were going through the pipe. There was a general circling and splashing and even somersaulting at the hole but none ventured through. There was no activity at all at the other end of the pipe where the passageway then leads directly to Slough Pond, though the water there is quite deep all along the channel. One of the wardens was alerted. As the alewives are intent on getting up to Slough Pond, and the Alewife Committee voted to keep the passage clear this year, regular maintenance will be necessary through the migration period. It is not anyone's intent to force the alewives away from Slough Pond even inadvertently.
Alewives on May 1st.
Water levels May 1st.
Culvert pipe, east and west.
May 2 There was less activity in the morning on May 2nd. The water levels remain high and fish are still coming and going in smaller groups, but there is no full flush of alewives gathering and circling at the culvert pipe. One of the wardens came by in the late afternoon and did a little clearing. He noted fish were getting through the pipe, one at a time, making their way toward the pond; 10 or so while he was there.
And tonight at dusk, under the almost full Flower Moon, a school of at least 50 fish moved across the surface of the pond together, feeding, their silvery bodies flashing in the half light. Could it be the alewives come home?
May 3 There were so many alewives rushing in today it was impossible to keep count and it was easy enough to let that idea go. The air and water temperatures were the same at 62° mid-morning; the earth and air and water pulsing with bright new life.
If there had been a blockage at the culvert pipe it was gone and fish were traveling through it unimpeded. There was an impediment farther on however. Just past the deepest section, measured last week at 13", the curve and straight run to Slough Pond was back to its shallow 2" at most. The fish were definitely avoiding it, choosing to stay in the deep, murky section once through the pipe. This shallowness is a result of sand build up. It is unfortunate it was not dug down (at a minimum of 3-5") before this migration peak. The rainfall last weekend improved the depth, allowing passage for many alewives, but only for a couple of days. A little more rain and a little judicious shoveling would help. More later...
May 4 And today, sorry to report that along with the same high number of alewives rushing in there was predation along the banks and in the stream itself. The alewives were still wary of the shallow passage toward Slough which they are unable to navigate successfully. See video below of one struggling in the shallow end, though he did turn back and make it safely to the depths again. The hindrance created by the shallow water no doubt increases the predation factor. There is always predation. Admittedly, it is a long stretch and a narrow stream In the woods open to raccoons, foxes, coyotes, fisher cats, stouts, even otters, though no gulls. Gulls make use of their vulnerability in the marsh, along Stony Brook Valley, and at the ladder itself. The bountiful alewife migration provides sustenance for all every spring after a long winter, as it once fed us and generations of Native peoples who introduced the early settlers to their many uses. However, water management and stewardship of the run, from one end to the other, it critical to their survival and the health of the entire ecosystem. On a more personal note, it is hard to see them struggling here.
"We will never know alewives until the motion, lift, light, weight, and changing beauty of the water is in some degree a part of us. In any case, we will never build the perfect fishway."
May 5 The Town's Department of Natural Resources and an alewife warden blocked the culvert today. They installed an open-ended bucket (which has its detractors) at the exit end of the culvert pipe and screening within the pipe to prevent the passage of the alewives toward Slough Pond. Access has already been encumbered by shallow water levels from lack of rain and water draw down and also from considerable sand accumulation. The fish adapted on a daily basis as rains came and went. Now their passage has been prevented in or out. Several local experts I spoke with did not support the use of this bucket.
It had been suggested that digging the channel out, earlier in the spring and even now, would be a more favorable solution. Other residents, we have heard, have raised their own concerns about decreased water levels in this and other ponds that effect their summer recreation, but balancing needs is effective stewardship, as we know. This blockage seems ill-timed. Although there were far fewer fish today, the run has only just begun, as far as entering the ponds beyond the fish ladder, and will continue for approximately another 4-6 weeks.
I don't think I am mistaken when I say that this decision is contrary to what was voted on at the February 23rd meeting (attended by 9 individuals) to keep the passageway open for further study this year. I hope this is a temporary measure, as the sign- Temporary Monitored Water Restriction- says, and daily, flexible oversight will follow, as I understand it will. Diverting the migration into Walker's Pond and eliminating Slough was mentioned as an earlier objective.
We have been asked by a warden to keep an eye on how the fish handle this blockage and we will. Already a dozen good sized alewives, notably older fish, no doubt returning to their natal pond, Slough, appear to be stranded between the blocked culvert and the sand bars, circling in a small school as they do.
Meanwhile, an otter graced the bright, pristine, blue waters of Slough Pond this afternoon, fishing.
May 6 Barely any fish in the passage today: a pair investigated the blocked culvert, there were signs of predation, and the stranded 12 were still circling in the deep waters beyond the pipe, prevented from passage either way. Blocking the culvert has decreased the water flow from the pond, therefore the entrance channel will shortly dry up, as there is no rain on the horizon. There was no evidence today of the easy flow of fish entering and exiting from Walker's Pond, even if they chose not to risk the blocked culvert, as was apparent yesterday. Alewives adapt quickly to changing conditions. Right now they are hovering around the mouth to the passage, waiting in Walker's, and hopefully not in vain, for their next opportunity to reach their natal pond, Slough Pond, if the fates will have it. Sunny, air temperature 72°.
May 7 The alewives have hatched out in Slough Pond. They have begun to school and are feeding on plankton. Judging by their size, these fry or fingerlings must be the spawn of our April 16-19 arrivals. We can expect more from the May 1-4 arrivals. Hatching occurs in 6 days if the water temperature is 62°, which it has been consistently. The fry will stay in the pond until at least early July though some will stay as late as November. Water levels in the passageway will factor into their departure date. These alewives will grow in strength and size with every month they stay in this their natal pond but they will not be fully mature until 3 years of ocean life. Slough Pond is one of the cleanest ponds on the Cape with a strong and healthy biodiversity to feed on so it will give them the best start of life they could have as a nursery habitat.
About spawning. Female alewives will deposit 60,000-100,000 eggs, about 0.05" in diameter, in shallow places along the edges of the fresh water pond where they themselves were born. The eggs sacks are called roe, pink or yellow/orange in color and sticky, they adhere to rocks and sticks. The males follow the females closely and scatter milt, a pinkish white substance, over the eggs and thrash it about with their tails to fertilize them. This makes for the splashing sound often heard during spawning season along pond shorelines. Roe is a favorite high protein meal for water snakes and eels, among other creatures, who also follow closely behind or wait among the rocks. Fertilized eggs hatch out in 3-6 days; 3 days or less when the water is 72° and up to 6 days when the temperature is 60°. Anadromous fish, such as alewives, live in the ocean but return to freshwater to spawn. Catadromous fish, such as eels, do the opposite. Together they are known as diadromous species, which migrate between fresh and salt water habitats and are adapted to both. Unlike salmon, alewives do not die after spawning but, once they have reached their maturity at 3 years, will return to their natal pond every year until their death to spawn. The majority of adult alewives, once they have spawned, will go back out to sea, but many linger for weeks to rest and regain their weight after the arduous journey inland. The young will stay in the ponds until they are larger, generally 3-4", before departing for their ocean life, anytime between early August and late November. We love watching the schools, numbering in the thousands it seems, circling and circling Slough Pond from spring throughout the summer and fall. They have numerous predators and can camouflage themselves by changing color as they move from sandy bottoms to murkier ones; and there is strength and protection in numbers. There has to be an annual survival rate, or escapement, of approximately 3-7% of the alewife fry, or fingerlings, to sustain a healthy alewife population from year to year. They face many challenges to that survival inland and at sea.
For more on how some areas are meeting the challenges of herring management and sustainability see our Resources page. Two plans are included for fishway management on two local ponds, provided by the MA Division of Marine Fisheries.
May 8 & 9 Now that the water is not flowing in the passageway due to the blockage, we can get a good look at the culvert pipe itself. It appears to be quite narrow with a jagged (possibly broken) sharp edge. On the west side of the pipe, toward Slough Pond, the stranded 12 have been reduced in number to 9 fish circling in the deeper, murkier recesses of the channel. And in the east, a few fish are still coming and going from the Walker's entrance though not attempting the culvert opening and not lingering for long in the passageway. The water level is not as shallow, for now, with no signs of predation evident.
Meanwhile, at the Stony Brook Fish Ladder itself (see below) the alewives are still arriving in good numbers, over 200,000 to date, bound for the inland ponds. This is all that most people see of the alewife migration, this splashy entrance, though those fortunate enough to spend time on the ponds can witness their progeny gaining in strength and number all summer long. And in late summer and throughout the fall, if you are lucky enough to catch them, watch as they turn and surrender to the pull of the stream, falling backwards down the ladder (not possessing the muscular strength of their parents). This is not something that should be missed. When asked about the alewives' contribution to nutrient loading in our ponds, Karen Malkus-Benjamin, Cyanobacteria Quality Control Manager for the APCC, told me recently, "Alewives’ contribution is a complex question. A lot of their impact depends on how many fish visit each year and the state of the pond where they are spawning." She provided two studies which I have included under Resources page.
News from Dennis... Bound Brook, in East Dennis, our nearest neighbor, is quite active with alewives arriving daily from Quivet Creek, which shares the marshland around Wing Island with Paine's Creek. Bound Brook is a lovely, quiet and well-maintained spot in the woods, replete with skunk cabbage and Baltimore Orioles in Wild Cherry trees, it is a fairly effortless passage for the alewives to make.
May 10 Today there were no fish entering the passage. Only 2 of the stranded 12 adult alewives were left in the deep water, the "ditch" as one warden called it, just past the blocked culvert. They were unable to go either way. These are large adults who have migrated here from the ocean and up the Stony Brook fish ladder to reach their destination, Slough Pond. Perhaps some had squeezed through the submerged bucket (see photo on May 5) and past the inserted screening but I doubt that is the case. One of the 2 showed signs of disease on his gills from the stagnant water. We were told the blockage was temporary and would be removed in a week. This is day 6. There has been no rain but the water level from the culvert to Walker's Pond is deep enough for passage.
May 11 A bespoke on my misspoke of yesterday. I spotted 4 stranded fish today, not 2. No other fish at all. While out in the woods I ran into Doug Erickson, a herring warden, Ryan Burch, of the Natural Resources Department, Kari Hoffmann, of the Select Board, and our Town Administrator Peter Lombardi. You never know who you will see down at the fishway these days. So that's something. Interesting article today in Down East Magazine on the "charismatic species" of alewives. Noting that the Damariscotta run was John Hay's home away from home. Article link.
And finally some thoughts on alewife scales, which John Hay likened to "iridescent coins." The alewives' silvery scales reflect sunlight and act as camouflage for the fish as they move through the water, additionally, the scales change color depending on the terrain beneath them. Our industrious forebears, in a great feat of Yankee ingenuity, sewed the dried scales onto cloth to make delicate evening purses. The age of a given fish can be counted on its scales in much the same way as one can gauge a tree's age by counting its rings. Neither can be done of course until the tree is felled or the fish is caught. I happened upon scales today scattered in a circle in a little mossy and enchanted area at the head of the entrance. Some animal or bird had enjoyed a quiet place for their feast. It made me think that if there were any woodland faeries about, if you believe in such things, they would certainly have fashioned these glittering scales into a cape or dress, or resplendent crown. Any five-year old child fond of creating fairy houses, and I know several, might advise that this is a fairy circle in and of itself- in the spirit of a little folklore for our pondlore site. Here is an interesting article on scales.
May 13 There is still a fair level of water at the entrance of the passage. Enough for fish to come in. However, there were no fish again today. Possibly, due to the obstruction at the culvert, they have learned they cannot get through, or the scent of their natal pond is not strong enough to attract them as the water is not flowing out. All of the stranded 12 adult alewives must have died. That is the only conclusion that can be reached unless, unbeknownst to me, someone captured the remaining fish in buckets of water and carried them to one of the ponds for release. There is no sign of any of them in the deep section where they were trapped nine days ago by the blockage, which we were told would be removed in a week. Only 4 were seen two days ago for the last time. The culvert is stilled blocked. The west end of the passage closest to Slough is riddled with sand shoals, the result of the channel not being dug out this year, or any recent year, coupled with the lack of precipitation, and draw down at the Stony Brook ladder.
Water level gauge at Slough Pond: April 1st thru May 13th sees a fluctuation of a high of 6.25 and a low of 4.5 for readings, though the mean average is a loss of only 1 unit in 6 weeks. At approximately 5.5 units or inches on the gauge during this period the water level in the fishway was deep enough for passage from east to west and into Slough, as noted in the journal entries above. The gauge was installed on March 31 at the Slough Pond landing by Alewife Warden Doug Erickson after conferring with Brad Chase of MA Marine Fisheries.. See Archive page for photos of the stable passageway conditions in 2019 and see also MA Precipitation Data Link.
We attended the Rights of Herring ceremony at the beautiful Mashpee Wampanoag Tribal Headquarters this afternoon, lead by the Wampanoag Youth Native Environmental Ambassadors. Very inspiring group of young people. See Resources for more information.
May 16 Field notes: A restive ramble in the woods today. The channel has so little water it resembles an old abandoned stream bed, with its own particular, if sorrowful, beauty. There were no fish in sight anywhere. There was pollen. There was wildlife. There was plant life. And there was the sound of quiet raindrops falling, Winter Moth caterpillars busy in the treetops nibbling away at all the tender new leaves. Two Catbirds chased each other along the passageway and stopped to bath in the shallows. Osprey called to each other overhead. Nesting swans were in their favored place across Walker's Pond, pure white against the blue and shadowed green. Bullfrogs leapt from mossy perches to hide in the deepest stretch of the channel, where they have taken up residence. Waves lapped on the shore of Slough in a brisk wind causing a stir of movement along the entrance that rippled away into the sandy shoals. The bucket that blocked the culvert (and sign) have been removed. Meanwhile down at the Stony Brook fish ladder, 46, 790 herring have arrived in the last week, bringing the total to 317, 428 this season. The run is not over. But we will need a good long rain to allow them passage into Slough Pond.
May 17 The water level is surprisingly high. Pictured is the eastern end of the passage between the culvert pipe and the entrance from Walker's Pond. Even without rainfall. It may be due to slightly increased water flow due to the removal of the blockage. Additionally, we experienced windy conditions on Tuesday which did cause some wave action on Slough Pond and renewed flow into the western end of the passage. The fishway is still quite shallow overall however. Rain is in the forecast and we remain hopeful. If you are on Instagram check out this video from Dennis Conservation Lands.
May 19 I mentioned the Dennis Conservation Land Trust (see LINK for more) the other day and have since received permission to share some of their wildlife "trailcam" video clips, collected as a data and educational resource. The clips you will see are from their Paddock Farm West Conservation area which includes a "manmade" fishway connecting Sesuit Harbor and Scargo Lake in East Dennis, our closest neighbor. This passageway was originally created to aid irrigation for cranberry bogs 200 years ago, has endured as a fishway (as are many on Cape Cod) and was recently restored to aid the alewife migration. It is a lengthy and often shallow passageway. You will see the biodiversity sustained by the alewife migration as well. The clips were recorded between March 22nd and May 5th of this year and feature raccoons, opossums, muskrats, deer, coyotes, otters, hawks, owls, herons, turtles, eels, robins, crows, and of course, center stage, the alewives. You will forgive me for including so many, but this is only 7 of 64 I marveled at. (I've tested these on 3 devices and it takes a couple seconds for each to cue up.)
May 21 We received 1.74 inches of rain from last night's storm. It has been enough to fill the entire passageway again. If there are any alewives lingering they will be able to make it into Slough for the next day or two. It is amazing what a little rainfall will do. The air was clear and fresh this morning, scented with pine and filled with bird song. Our hearts were lightened too. There was evidence of a great deal of stormwater runoff from the dirt road and pathway into the culvert area as well as sand run off from the pond itself at the headwaters entrance. Even this recent accumulation though, added to what was already present, has not prevented the water from flowing freely again. The last herring seen in our fishway was on May 9, however the schools were unable to access Slough Pond due to low water levels throughout most of the passageway from long-standing sand accumulation, last of precipitation, and the bucket blocking the culvert pipe from May 5th thru May 16th. Remembering that 46,790 alewives were counted at the Stony Brook fish ladder between May 9-16, they are still out there.
May 22- 25 We are considering weekly installments going forward as, for now, there is minimal change at the fishway. There were no fish on Monday, though the water level had held well. On Tuesday, there were two dead herring who had evidently been predated while entering the passage. By Wednesday, the water level had returned to its earlier shallows, with no perceptible flow coming through the culvert pipe and the two beheaded fish had disappeared. There is some good news however, spawning was evident on either side of the entrance from Walker's by the old fallen tree. Many adult alewives could be seen, and heard, circling and splashing in the shallow water along the shoreline and among the low lying branches, though it was too murky to photograph well. (See video below.) And for another low light photographic challenge, a lone White-tailed deer was seen grazing along the shoreline just past sunset. Please note, if you find scientific studies of interest, I added a fascinating new study under Resources on juvenile herring, with permission from its author at the Department of Environmental Conservation, UMass/Amherst. Meanwhile, down at the fish ladder the electronic herring counter has been removed, possibly for the season, due to technical issues. There were large numbers of adult herring still coming in and many also emigrating back out which caused a backup at the counter in the seining pool. The impressive figure of 405,880 herring, nearly half a million, was posted for the period from March 20 thru May 19 on the Stony Brook Grist Mill white board. Just because the counter isn't counting them the run is still not over! Next week I plan to post "May Notes" as I did last month, a bulleted list of the month's observations and considerations. Finally, for the holiday upon us, two favorite fish poems: The Fish, by Elizabeth Bishop and The Fish, by Rupert Brooke.
May 30 Walked the passage this morning with a colleague and found it basically unchanged as far as lack of fish and shallow water levels. We noted the rather deplorable condition of the exposed culvert pipe and the bank erosion. The Fiddlehead Ferns were lovely though in their full glory. No activity noted of spawning along the shoreline at all. We found deer tracks and raccoon prints in the sand, possibly a few fast moving frogs or toads (Fowler's toads have begun calling at night), a diminutive snake (Garter or Ribbon) , one dead alewife, at least one mosquito. Farther down, we did note large schools of adult herring circling at the entrance from Slough but unable to come into the passageway, which was blocked by sand accumulation, as noted in earlier posts. But that was this morning. We had run into the Cape Cod Mosquito Control Project (CCMCP) crew during our morning tour, checking for mosquito larvae. Whether through coincidence, serendipity, or synchronicity, we often run into others in the woods at just the right moment. They told us they do clear the passageway out every 3 to 5 years depending on their rotation schedule but had not cleared it this spring. Their primary control mechanism for mosquitos is water management, i.e., "selective ditch maintenance" to monitor and alleviate standing water as breeding areas. They have jurisdiction under the State of Massachusetts. Their presence is a common occurrence on our road due to the wetlands, now nearly dry. The water level gauge installed by the Alewife Committee at the Slough Pond landing now reads 4 inches. But lo & behold, things had changed dramatically after lunch. The water was now flowing freely again in the fishway, which seemed curious. I walked it again. Apparently, the crew, of two, had done some serious digging at the Slough entrance - about 12 yards along the fishway, lowering the channel down 5 inches. The adult alewife schools we had seen in the morning were now entering the passage, rather eagerly, or so it seemed, but once they reached the shallows farther down, after the initial 12 yards, they turned back. It was hard to say how many adults were present, but at least 100.
May Notes:
Hundreds of adult and juvenile alewives are seen in Slough Pond, having made it through the Walkers/Slough fishway under challenging conditions and in a very limited time frame and spawning occurred
The fishway was essentially closed through neglect, though voted to be kept open, by not fostering optimal conditions in time for the migration
There were only 3 good days for the fish migration from Walkers to Slough, in the period May 1-3 (there were also 3 good days in April)
There was no passage available for most of the month, due to low water levels, sand accumulations, and the culvert being blocked for 11 days, in the period May 4-31
Rain would have aided the passage but there has been little this month
Questions to consider:
If keeping the fishway open is a manpower issue, why not accept the help that has been offered?
If the issue is concern for the welfare of the alewives, why not assist their migration rather than prevent it?
If the issue is the effects of climate change, isn't it better practice to seek adaptive, proactive, flexible solutions rather than defeatist ones?
What effects will its closure have on the ecosystem, in fact, the entire watershed? Further study is required
It might be too easy to feel discouraged with what has unfolded here in the past three months since we began our journey on this website. But we can envision a better future by keeping in mind Wallace Stegner's beautiful phrase, "the geography of hope." If we ever needed evidence that our hearts and our minds are in the right place on these issues, read the NOAA River Herring Habitat Conservation Plan published May 25, 2023. It calls for, among other things, education, raising awareness, forming partnerships, seeking wide-ranging professional expertise, and working with a management plan, that includes an alternative analyses study. For some lighter reading, or for story time, look for The Adventures of Allie the Alewife, a picture book for children, written by biologist Barbara Brennessel and illustrated by Marisa Picariello, published in 2015, in support of the Herring River Restoration Project, Wellfleet, MA. One copy is available at the Eastham Library.