May 1
Hundreds of alewives arriving at the passage today, whereas yesterday we observed only a pair. They dash back and forth in the stream, their color seeming to change right before your eyes, from silver to gold to gray as they pass; all translucent and iridescent in today's low light. Their feathery fins are wing-like and and in constant motion, splashing, twirling, practicing their spawning moves. Only two ventured through the culvert while I was there. It was the same yesterday. They are wary of that long stretch of darkness. Who knows the interior conditions of that ancient pipe? The gauge read just below 5" and there are some shallows here and there, as we await more rain. The NRD canoe was out on the pond yesterday; their sampling has begun.
Where the wild things are...there was a single frog leaping into the water and deer tracks again along the muddy path. Yesterday I spooked a large White-tail who scampered off into the cover of the trees. Today, I finally spotted the Wood Duck out on the pond who I have heard calling for the past several nights, his lone cry punctuating the night chorus of the peepers.
Hundreds of alewives arriving at the passage today, whereas yesterday we observed only a pair. They dash back and forth in the stream, their color seeming to change right before your eyes, from silver to gold to gray as they pass; all translucent and iridescent in today's low light. Their feathery fins are wing-like and and in constant motion, splashing, twirling, practicing their spawning moves. Only two ventured through the culvert while I was there. It was the same yesterday. They are wary of that long stretch of darkness. Who knows the interior conditions of that ancient pipe? The gauge read just below 5" and there are some shallows here and there, as we await more rain. The NRD canoe was out on the pond yesterday; their sampling has begun.
Where the wild things are...there was a single frog leaping into the water and deer tracks again along the muddy path. Yesterday I spooked a large White-tail who scampered off into the cover of the trees. Today, I finally spotted the Wood Duck out on the pond who I have heard calling for the past several nights, his lone cry punctuating the night chorus of the peepers.
May 2 & 3
Two more strong migration days at the passage. If you look closely you will see herring entering Slough Pond through the new sandbag weir. The unfortunate yellow hue of the images reflects spring's early color, the sand, and the occasional tannic effect of the stirred up stream bed.
Two more strong migration days at the passage. If you look closely you will see herring entering Slough Pond through the new sandbag weir. The unfortunate yellow hue of the images reflects spring's early color, the sand, and the occasional tannic effect of the stirred up stream bed.
May 4
I have never seen such a run as this year's. Six days and counting, with the two in April, in which hundreds of herring are migrating into Slough. The numbers are not so high this year as last down at the ladder, 85,238 today compared to 270,638 May 9, 2023.
Not to be discouraged by these numbers- it is likely the run will continue through the month of May as it was delayed in March and early April due to high water levels and low water temperatures. The Blueback Herring (alosa aestivalis) has probably caught up with the Alewife (alosa puedoharengus), as they travel a month behind. Both are river herring, though different species. It is likely both have entered the Slough Pond passage, considering the slight difference in color, size, and movement in the present schools. The Blueback prefer to spawn in moving water and there has been what looks and sounds like spawning in the stream. The Alewives prefer still water and continue on to the pond for spawning. According to a visiting herring expert, there is occasional interbreeding between the species, which does seem hard to avoid.
I have never seen such a run as this year's. Six days and counting, with the two in April, in which hundreds of herring are migrating into Slough. The numbers are not so high this year as last down at the ladder, 85,238 today compared to 270,638 May 9, 2023.
Not to be discouraged by these numbers- it is likely the run will continue through the month of May as it was delayed in March and early April due to high water levels and low water temperatures. The Blueback Herring (alosa aestivalis) has probably caught up with the Alewife (alosa puedoharengus), as they travel a month behind. Both are river herring, though different species. It is likely both have entered the Slough Pond passage, considering the slight difference in color, size, and movement in the present schools. The Blueback prefer to spawn in moving water and there has been what looks and sounds like spawning in the stream. The Alewives prefer still water and continue on to the pond for spawning. According to a visiting herring expert, there is occasional interbreeding between the species, which does seem hard to avoid.
Slough Pond passage at culvert today.
Stony Brook fish ladder at Lower Mill Pond today.
May 6 & 7
Two beautiful spring days and our stream was filled once again with herring making their way into Slough Pond and fiddlehead ferns and mayflowers unfurling along the banks.
Two beautiful spring days and our stream was filled once again with herring making their way into Slough Pond and fiddlehead ferns and mayflowers unfurling along the banks.
May 8
The herring are still running strong at the passage. The rainfall may help keep the water level up for the rest of the week, though the pond level, as measured by the gauge, is considerably lower, at barely 4." It's possible a few adults were seen departing.
The first flowers are appearing in the woods on the Mayflower and Star Flower plants, diminutive yet ubiquitous. Florets are opening on the wild blueberries, replete with our local pollinating Bumblebees. And even the velvety moss that cloaks old tree stumps is sprouting miniature blossoms all its own. Of course, the Shadbush is in full bloom. A pair of Catbirds, who arrived this week, were foraging along the bank. If it is the same pair, they had a nest tucked into the woods close to the passage last year. Also new today, for the first time I was able to witness herring circling within the culvert pipe.
The herring are still running strong at the passage. The rainfall may help keep the water level up for the rest of the week, though the pond level, as measured by the gauge, is considerably lower, at barely 4." It's possible a few adults were seen departing.
The first flowers are appearing in the woods on the Mayflower and Star Flower plants, diminutive yet ubiquitous. Florets are opening on the wild blueberries, replete with our local pollinating Bumblebees. And even the velvety moss that cloaks old tree stumps is sprouting miniature blossoms all its own. Of course, the Shadbush is in full bloom. A pair of Catbirds, who arrived this week, were foraging along the bank. If it is the same pair, they had a nest tucked into the woods close to the passage last year. Also new today, for the first time I was able to witness herring circling within the culvert pipe.
The herring count at the fish ladder now stands at 127,115. Today, national senior officials from the Natural Resources Conservation Service, Watershed Operations- who provide funding for Cape Cod Water Resources Restoration Projects across the Cape, including the scheduled repairs and improvements at the Stony Brook (Watershed) fish ladder (slated to begin in November)- visited the fish ladder and mill. This federal organization is the funding source of 75% of the $1.2 million project, the remaining 25% being by the Town of Brewster. Town Manager Peter Lombardi toured the site with the group, along with Charlie Sumner, Natural Resources Director Chris Miller, who provided a design presentation, and Warden Doug Erickson.
May 9
The herring are still present in large numbers, however, they are struggling now to get past the shallow area on the stretch about 200 feet down from the pond. I watched as two tried it out, then turned back, followed a few minutes later by four who turned back at the same spot. They will wait for any advantage the intermittent rain will bring, gathering together, resting, and feeding in the stream.
The herring are still present in large numbers, however, they are struggling now to get past the shallow area on the stretch about 200 feet down from the pond. I watched as two tried it out, then turned back, followed a few minutes later by four who turned back at the same spot. They will wait for any advantage the intermittent rain will bring, gathering together, resting, and feeding in the stream.
Attended a talk at the CCMNH today given by local author Stephen G. Waller. His book, A Moving Meditation, Life on a Cape Cod Kettle Pond is well researched and a personal narrative of life on Long Pond in Centerville. He and his wife Jane are alewife enthusiasts, as a small herring run skirts their yard. It was interesting to hear a first-hand account of how a "manmade" fishway (in the 1850's) is managed in Barnstable.
Also stopped by Bound Brook and spoke with a volunteer who was there counting fish. She told me the run, though late, has been strong this spring, also over at Scargo Lake. She worried about the herring making their way up into the pond getting dashed against the rocks that form the natural ladder there. The current was not forceful but as I watched some flipped over entirely on their backs against the rocks- the surprise of their bright silver scales and dark eyes so entirely out of the water- being swept back into the churning brook, then forcing themselves forward again. I had never seen them having this sort of trouble before. Smooth river stones might make a good replacement. Beyond this evident struggle, the small hidden woods there never fail to be enchanting.
Also stopped by Bound Brook and spoke with a volunteer who was there counting fish. She told me the run, though late, has been strong this spring, also over at Scargo Lake. She worried about the herring making their way up into the pond getting dashed against the rocks that form the natural ladder there. The current was not forceful but as I watched some flipped over entirely on their backs against the rocks- the surprise of their bright silver scales and dark eyes so entirely out of the water- being swept back into the churning brook, then forcing themselves forward again. I had never seen them having this sort of trouble before. Smooth river stones might make a good replacement. Beyond this evident struggle, the small hidden woods there never fail to be enchanting.
May 10 & 11
After their scouting parties on the 9th, the herring are no longer swimming past the curve in the passageway that leads to the pond. This area has become too shallow for them, as this stretch often can. A warden came by and dug this area out and adjusted the sandbags for water flow. We do not expect enough rain to raise the level in the stream in the next few days, so we will keep an eye on the fishes' movement- maybe the weather will surprise us. There are still fish coming into the passage, more yesterday than today, but these arrivals stay in the small pool by the culvert, whereas yesterday many were in the deeper area just past it. They appear to be spawning in both areas as they await their chance to get up to the pond. The water is not flowing in the stream so it is most likely alewives and bluebacks. It was not surprising that the gauge measured a much lower reading, 3.25" this morning, as the fish usually start having trouble at 4."
We checked out the Pine Pond connection again today and noted that one of the two culverts is definitely blocked, as usual, but the other, smaller one has a good water flow into Slough. The Barnstable County Mosquito Control crew, here last week, might have cleared it of debris. This bog and pond front is conserved by the Brewster Conservation Trust, among its 9.3 acres either directly on Slough Pond or within its watershed. Friends on the Brewster Ponds Coalition should be able to tell us if they spot any alewives in Pine Pond this year, migrating in from Slough. And this is hearsay, but we have heard that the connector to Canoe Pond might actually be viable. We plan on looking into this and also the Elbow Pond connection in the coming weeks. It is our hope that all seven of the headwater ponds of the Stony Brook Watershed (not 3, 4, or 6) will be maintained as viable herring habitat and nurseries.
May 12
Only a handful of fish today with none going through the culvert heading toward the pond. So far we have had 9 strong days this month- in a row- and 2 late last month, which totals 10 very strong migration days. If this is the tail end of things, it has been a great run, but we hope it's not over yet. Last spring we also had a 10 day run but it was intermittent and spread out between April and May. Looking back on last spring's migration, we are sadly reminded of the many difficulties we faced: lack of maintenance in the passage, leaf litter, sticks, and accumulated sand causing very shallow areas for the fish to migrate through; this coupled with sand buildup at the culvert, from the road runoff, and the bucket installed by a warden to block the culvert for 12 days! Things are looking up this year. Due to maintenance in the fall and earlier this spring, with the addition of the sandbag weir for water control and abundant rainfall, many more herring came in easily. It has been a happier run for all concerned though the future protection of this herring run is still in question. For the many hundreds of alewives who reached their natal pond to spawn this year, any day now we expect to see their progeny beginning to school in Slough Pond.
Only a handful of fish today with none going through the culvert heading toward the pond. So far we have had 9 strong days this month- in a row- and 2 late last month, which totals 10 very strong migration days. If this is the tail end of things, it has been a great run, but we hope it's not over yet. Last spring we also had a 10 day run but it was intermittent and spread out between April and May. Looking back on last spring's migration, we are sadly reminded of the many difficulties we faced: lack of maintenance in the passage, leaf litter, sticks, and accumulated sand causing very shallow areas for the fish to migrate through; this coupled with sand buildup at the culvert, from the road runoff, and the bucket installed by a warden to block the culvert for 12 days! Things are looking up this year. Due to maintenance in the fall and earlier this spring, with the addition of the sandbag weir for water control and abundant rainfall, many more herring came in easily. It has been a happier run for all concerned though the future protection of this herring run is still in question. For the many hundreds of alewives who reached their natal pond to spawn this year, any day now we expect to see their progeny beginning to school in Slough Pond.
To pose a question- what is the best use of the sandbags now?
They were useful for controlling the water flow into the passage after the abundant early spring rain, shifting them a few times to adjust the flow over several weeks. But now what?
They were useful for controlling the water flow into the passage after the abundant early spring rain, shifting them a few times to adjust the flow over several weeks. But now what?
- Should the sandbags be positioned to block the passageway soon? This would prevent any adults from leaving the pond, if they haven't already, until the water level in the channel is adequate for their emigration. The channel will dry up over the summer months. The juveniles will not leave until late August. It is doubtful it will fill up with or without the sandbags until late summer.
- Should the sandbags be removed? Any fish attempting to leave would turn back, as I have seen them do, if the channel lacks adequate depth. According to one of the Barnstable Mosquito Control crew, he would prefer the stream remain natural, as a vernal stream, without interference; the crew is required to keep such passageways free of standing water that breeds insects. What insights can they offer?
May 13
Nary a fish today.
Nary a fish today.
May 17
After a four-day absence, the herring were back today. This is a new wave of late migrants; they are running at the ladder as well. We received a full inch of rain yesterday, which brought the pond level up that inch, a more comfortable level for the fish to navigate in the passageway. Someone had moved the sandbags, which effectively closed the entrance to Slough, possibly to raise the water level in the stream (or perhaps thinking the run was over). They were shifted today. The channel has lost some of its depth but it is still navigable.
Upon arrival from Walker's, the herring gather below the culvert pipe in the small pool, as they do, before venturing through the pipe. Usually two or three strike out beyond the curve making their way to Slough. A few turned back today when they sensed shallower areas there, as they often do, but others stayed the course.
After a four-day absence, the herring were back today. This is a new wave of late migrants; they are running at the ladder as well. We received a full inch of rain yesterday, which brought the pond level up that inch, a more comfortable level for the fish to navigate in the passageway. Someone had moved the sandbags, which effectively closed the entrance to Slough, possibly to raise the water level in the stream (or perhaps thinking the run was over). They were shifted today. The channel has lost some of its depth but it is still navigable.
Upon arrival from Walker's, the herring gather below the culvert pipe in the small pool, as they do, before venturing through the pipe. Usually two or three strike out beyond the curve making their way to Slough. A few turned back today when they sensed shallower areas there, as they often do, but others stayed the course.
May 18 & 19
The fish keep coming in, not by the hundreds, but the thousands it seems. Spawning is in full force all along the channel and along the edges of the pond. The water temperature is 62° (warmer than the air temperature) so eggs fertilized this weekend should hatch in about five days, to join the fry hatched earlier this month. It is an amazing thing to have a front row seat to this miracle of their return to their home waters, not just the struggle in, but the creation of their next generation. Watching them here, we are grateful that they did not lose this precious habitat last year. They have reclaimed it in full force from one end to the other. It is abundantly clear that the proper maintenance of this passageway last fall and this spring has supported the herring migration this year with remarkable effect, even with the low gauge reading of 4," which is just enough for their safe passage. The total counted at the Stony Brook fish ladder is 143,467 herring, minus the count of a couple days when the counter was removed (371,569 in Harwich). It is a much lower count this year, but not here, where it is considerably higher- the fish are here.
The passageway is black with migrating herring in the deeper, tannic, "tea dark" sections, like in years gone by from what I have heard. Waves are kicked up by their spawning activity here, as their small fins cruise above the surface like miniature sharks. They are beautiful fish, delicate in form and color. They are "made for water" as John Hay has written and seem to fly through it, changing color from one place to the next- once grey, then silver, buff, then brown, green, now pink. As they circle along the pebbled shore, where the low hanging branches and the deep green moss touch the water of their natal pond, I am reminded that he called their spawning "the dance." It is a privilege to observe.
The fish keep coming in, not by the hundreds, but the thousands it seems. Spawning is in full force all along the channel and along the edges of the pond. The water temperature is 62° (warmer than the air temperature) so eggs fertilized this weekend should hatch in about five days, to join the fry hatched earlier this month. It is an amazing thing to have a front row seat to this miracle of their return to their home waters, not just the struggle in, but the creation of their next generation. Watching them here, we are grateful that they did not lose this precious habitat last year. They have reclaimed it in full force from one end to the other. It is abundantly clear that the proper maintenance of this passageway last fall and this spring has supported the herring migration this year with remarkable effect, even with the low gauge reading of 4," which is just enough for their safe passage. The total counted at the Stony Brook fish ladder is 143,467 herring, minus the count of a couple days when the counter was removed (371,569 in Harwich). It is a much lower count this year, but not here, where it is considerably higher- the fish are here.
The passageway is black with migrating herring in the deeper, tannic, "tea dark" sections, like in years gone by from what I have heard. Waves are kicked up by their spawning activity here, as their small fins cruise above the surface like miniature sharks. They are beautiful fish, delicate in form and color. They are "made for water" as John Hay has written and seem to fly through it, changing color from one place to the next- once grey, then silver, buff, then brown, green, now pink. As they circle along the pebbled shore, where the low hanging branches and the deep green moss touch the water of their natal pond, I am reminded that he called their spawning "the dance." It is a privilege to observe.
Fry Facts:
- during each spawning event, females shed, or broadcast, eggs (roe) in the 10's -100's of thousands
- eggs are adhesive and cling to rocks
- males shed, or broadcast, sperm (milt) over the eggs and scatter it with their tails
- spawning occurs when water temperatures reach approx. 50°
- unfertilized eggs are greenish and fertilized eggs are amber
- eggs and larvae need oxygen in the water to survive
- eggs hatch in 6 days at 60° water temperature, 2-3 days @ 70°
- larval stage is 2-3 weeks depending on temperature
- the fry (fingerlings, juveniles, or progeny) are 0.78" at first
- fry are phototrophic- they soak up sunlight
- their natal pond is their nursery
- fry eat plankton
- when fry reach 1.2" they are replicas of the adults
- as they grow they begin to school to protect themselves from predators
- when they are large and strong enough at 2"-4" they begin to depart for the sea
- they emigrate from late summer to early winter in intermittent pulses
- for the herring species to survive they must have an escapement of 3-7%
- after 3-4 years at sea they will return as adults to their natal pond- How? The otolith.
- river herring can live for 10 years
May 20
Numerous fish were gathered by the culvert pool and dashing in and out of the passage from Walker's, but today none ventured beyond the culvert to Slough. There was as much water in the stream as the day before, but marginally so. It was interesting again to see how quickly the fish change color as they swim above different surfaces. Flora continues to flourish along the moist, sun filtered, and sheltered banks, Sensitive Ferns have now joined the Star Flowers, Mayflowers, and Fiddleheads. There has been very little predation along these banks, only a few scatterings of iridescent scales, little white stars in hidden alcoves, where an animal or bird may have feasted. I have seen only one dead herring this year and he showed no marks of trauma.
May 21
There were no fish in the passage today, only shadows. Perhaps the migration here has run its course. The gauge at the landing has dipped into the impossible to pass range of 3.5." Down at the fish ladder the season count now stands at 151,936 herring.
Nevertheless, the enormous number of migrating alewives returning to the Slough Pond passage have been the talk of the neighborhood all month. So many people expressing joy at seeing the fish in such great abundance again!
There were no fish in the passage today, only shadows. Perhaps the migration here has run its course. The gauge at the landing has dipped into the impossible to pass range of 3.5." Down at the fish ladder the season count now stands at 151,936 herring.
Nevertheless, the enormous number of migrating alewives returning to the Slough Pond passage have been the talk of the neighborhood all month. So many people expressing joy at seeing the fish in such great abundance again!
May 22
Possibly the first of the alewife fry spotted this morning. So tiny, mere shadows and almost invisible, they resolve in and out of vision.
Possibly the first of the alewife fry spotted this morning. So tiny, mere shadows and almost invisible, they resolve in and out of vision.
May 24
Neighborhood watch! Thanks Abby & Matt for this video of the adult and juvenile herring swimming in Slough Pond this morning. And, although I had not observed any fish in the passage since the 20th myself, another neighbor informed me other neighbors saw quite a few herring there today.
Neighborhood watch! Thanks Abby & Matt for this video of the adult and juvenile herring swimming in Slough Pond this morning. And, although I had not observed any fish in the passage since the 20th myself, another neighbor informed me other neighbors saw quite a few herring there today.
May 26
After a few days with no new arrivals, and thinking the run was over, how surprising it was to see a huge influx of fish this morning. This has certainly been an interesting year. The pond level, at 3," is still quite low, though there is adequate depth in the passageway, with some shallower stretches. Today, as on previous days, the fish were gathered in the area that leads from Walker's to the culvert and also just past the culvert pipe, in the deepest area of the channel. None had ventured beyond the curve that leads to Slough. We have observed this behavior more than once this season. I will check again later to see if some scouts complete navigating the passage.
It is fairly evident that there is spawning activity in the small pool and along the stream on either side of the culvert pipe, as there has been on other days. There could be bluebacks (Alosa aestivalis)along with alewives (Alosa pseudoharengus) here, especially so late in May, and as they do tend to spawn in these areas rather than the pond. I have heard that It is nearly impossible to discern a visible difference between the two river herring. Also challenging is the fact that herring change color under different conditions, as we have noted before.
After a few days with no new arrivals, and thinking the run was over, how surprising it was to see a huge influx of fish this morning. This has certainly been an interesting year. The pond level, at 3," is still quite low, though there is adequate depth in the passageway, with some shallower stretches. Today, as on previous days, the fish were gathered in the area that leads from Walker's to the culvert and also just past the culvert pipe, in the deepest area of the channel. None had ventured beyond the curve that leads to Slough. We have observed this behavior more than once this season. I will check again later to see if some scouts complete navigating the passage.
It is fairly evident that there is spawning activity in the small pool and along the stream on either side of the culvert pipe, as there has been on other days. There could be bluebacks (Alosa aestivalis)along with alewives (Alosa pseudoharengus) here, especially so late in May, and as they do tend to spawn in these areas rather than the pond. I have heard that It is nearly impossible to discern a visible difference between the two river herring. Also challenging is the fact that herring change color under different conditions, as we have noted before.
Returning later in the day, all the fish observed this morning were gone, which was quite a surprise. As I scouted the passage for them, I spotted four or five simply swimming in and out by the entrance at Walker's Pond. The tree pollen cast a golden hue to the water; I spotted an Osprey cruising overhead, was serenaded by the Catbird couple, disturbed a Green Heron, and a frog, or possibly a Fowler's Toad, a screeching chorus of which echoes across the pond every night now from this vicinity.
May 28
No fish anywhere in the passage today, during my visit at least. We received a full inch of rain from last night's storm, adding to the stream's level, so any adult herring could probably have emigrated out if they wanted to. There was evidence of heavy run off from the dirt road, strong enough to shift and overrun the sand bags there. Some debris made it as far as the culvert.
The final count at the fish ladder was posted today and the numbers were low:
Take note: The electronic counter may have been removed at the Stony Brook fish ladder, closing their count for the season, but citizen science volunteers are asked by the APCC to keep counting herring at designated locations across the Cape until June 15th.
No fish anywhere in the passage today, during my visit at least. We received a full inch of rain from last night's storm, adding to the stream's level, so any adult herring could probably have emigrated out if they wanted to. There was evidence of heavy run off from the dirt road, strong enough to shift and overrun the sand bags there. Some debris made it as far as the culvert.
The final count at the fish ladder was posted today and the numbers were low:
- 2024 @ 154,231
- 2023 @ 266,630
- 2022 @ 108,737
- 2021 @ 103,401
- 2020 @ 206,123
- the passageway is approximately 900 ft
- I counted approx. 10 herring every 3 feet along the entire passage during the heavy migration
- there were 14 strong migration days from April through May
- the total estimated count on those 14 days comes to 42,000 fish/ which is 3,000 fish each day for 14 days
- there were 6 additional migration days with fewer but still numerous fish
- we can estimate 1/3 the number of fish on those 6 days which totals 6,000 fish/which is 1,000 fish for 6 days
- the grand total from the 20 days comes to 48,000 herring utilizing the passage during the 2024 season
Take note: The electronic counter may have been removed at the Stony Brook fish ladder, closing their count for the season, but citizen science volunteers are asked by the APCC to keep counting herring at designated locations across the Cape until June 15th.
