The following represents: (1) hypotheses about why the Alewife Herring population has steadily declined, resulting in no observed Alewives by us in 2004, as well as (2) some discussion of the evidence and (3) preliminary proposals for research about conditions and pollutants that have negatively impacted Alewife health and reproduction and lack of movement into the Alewife Brook and Reservation. 

A.   10 Theories of what happened

I.                    The connecting waters from the Mystic, Alewife Brook and Little River, including Perch Pond are too shallow. 

Ia.        Water temperature is too high.

Ib.        Dissolved Oxygen in that water is too low.

Ic.        Flow is too slow. 

II.                 There is too much suspended clay in connecting waters. 

III.               Something went wrong 3 years ago; i.e. silt covered the eggs.

IV.              Mystic River to Mystic Lake population was low or people took too many. 

V.                 Coastal population low. 

VI.              The dam operators failed to pass fish through locks before they were eaten. 

VII.            Carp and other predators.  

VIII.         Chemicals used on Spy Pond and maybe also at Little Pond are damaging. 

IX.              Pollutants deposited from Purecoat North, stormwater, sewer water, and from rainfall—such as Mercury—may have had a negative effect on fish reproduction and health.

X.                 Bacteria from sewer water that comes into the Little River and Pond and Alewife Brook from the storm-pipes may have a significant negative effect on fish health and reproduction.

B.    Evidence supporting or negating the above theories.

I.                    too shallow: In the early years we canoed without difficulty and paddled up Wellington Brook to the stormwater outfall pipe.  On June 30 this year, we had difficulty passing through sections of the Alewife Reservation.  I estimated the depths. to be as follows: Perch Pond, Cambridge: 6”; Perch P. to Bullfinch buildings: 8”; along those buildings and the DCR parking area: 6”; just above Alewife station access road bridge: 4”; Mass. Ave. bridge: 6”; Henderson St. bridge: 5”; below Broadway for a canoe-length: 3”.  Other sections: 1’:  Wellington Brook depth, lower and middle appeared adequate ’04; We will compare these depths with other herring runs and literature.

     The above observations were for one day only, after a period of low rainfall. Therefore, they are not representative of the average level of water in Alewife Brook, Little River, and Little Pond.  For example, the depth of the water beneath the Mystic River Parkway bridge in Arlington, near the mouth of Alewife Brook, was 3 feet on September 30, this year, as measured using a weight attached to a fishing line by Ralph. 

Ia         too warm:   ’04 water temperature reached high early, then cooled, warmed.  Global warming has caused a small increase in water temperature, resulting in an average increase of water temperature by 1 degree Fahrenheit over the last century.  It is not known whether this small temperature increase has negatively impacted Alewife health or runs up the Alewife Brook.

Ib         low DO, Dissolved Oxygen.:  CSO’s  discharged in ‘04; though situation is improving; compare results of MyRWA samples for dates of herring present in 2001, 2, and 3.  DO reading at Alewife Brook near the mouth, near the Mystic from permanent EMPACT monitor on 9.13.04 showed a DO of 5 mg/kg.  This is equal to a quantity of dissolved oxygen of 5 PPM, 5 parts per million.  In a metric ton of Alwife Brook water, there was 5 grams of dissolved oxygen.  According to Julie Horowitz, a DO level of 3 or below may be fatal to fish.  So although the DO level at Alewife near the mouth was adequate for survival, it was on the low side and may have had ill health effects on Alewives and other fish.  By contrast, the monitor at Sandy Beach on the same day showed a DO of 8 mg/kg.  As several schools of Herring fingerlings were observed by us at the dam, on the Lower Mystic side, while none were observed in the Alewife water, we feel that the lower DO in Alewife waters may be responsible for the lack of fingerlings.

 

Ic         low flow:  flow was above average in ’04; good in Wellington Brook; estimate flows at various locations.  Request from Belmont Recreation Dept. the dates and amounts of Claypit Pond withdrawals;

 

II.                 turbidity:   ’04 clear around Winn Brook culvert, very turbid elsewhere; in sample collected, note time for silt to settle.

III.               past failure:  monitor and record observations of fingerlings.

IV.                   

low numbers in Mystic:  ‘04 Brad chase reports that the Mystic run was below average this year.  As the Alewives return from the ocean via the Mystic River, this would have had a corollary effect of lowering the number of Alewives going up Alewife Brook to Little Pond.   Stew asked DCR Commissioner of Dams for Earhart Dam staff to note numbers and compare over years; study effect of enabling fish to pass around the Mystic Lakes dam; study report to see what strategy attracts herring to fish ladder; look for herring entering sluiceway at Lakes dam; work with Friends of the Upper Mystic Lake, Friends of Mystic River, and the Watershed Association.

Using flat stone at foot of Lakes dam, take measurements of water levels

V.                  

low numbers along coast and other rivers:  ‘ 04 Roger Frymeier reports numbers were unusually low in the Charles and Ipswich

 

VI.              Earhart Dam passage inadequate:  Nick Winters, head of Earhart Dam staff, died last year; he had great interest in the herring.

VII.            Carp and other predators: Jim Burnham’s research tentatively concluded that given the number of eggs produced by herring, carp predation would not be significant;** Mr. Jacobsmeier at Arlington Fish and Bait, reports illegal activity at the Lakes dam, people before dawn using large nets from boats taking herring. A Black Crappie sunfish was found near fingerling area in the Lower Lake; these feed on small fish.

VIII.         Chemicals applied for pond weeds:  The City of Arlington applied weed killer at/on Spy Pond in ‘04

IX.              A.  Purecoat North.  Several documented spills from the metal coating factory, Purecoat North, have occurred in the last decade, including at least one 55 gallon barrel of Hydrochloric acid.  The acid may have reached the groundwater before being cleaned up and, thus, reached Wellington Brook and Little Pond.  Although pH data supplied to us by Julie Horowitz for 2001, ’02, and ’03 showed that the water was either neutral as far as acidity or basic, spills in the past may have caused temporary increases of acidity or caused temporary poisoning of fish and algae or increased the chlorine level in Little Pond and River.

B.      No Mercury measurements are known to exist for the Alewife waters.  However, it is known that all natural water bodies in the 48 states have some mercury in them due to mercury emitted from stacks of coal-fired electric power plants.  Specifically, with regard to Massachusetts, the DEP conducted a study published in May, 1997 entitled Fish Mercury Distribution in Massachusetts Lakes, Final Report, by the Office of Research and Standards, Wall Experiment Station, and the Office of Watershed Management.  The researchers measured the amount of Mercury in more than 150 samples of each of 3 fish species in water bodies that are probably the least impacted by pollution in Massachusetts.  The water bodies were in the far Western part of the state, the Northwestern area North of Worcester, and the Narragansett/Bristol Lowland South of Boston.   Despite the fact that these water bodies were less impacted by urbanization and pollution than the Alewife waters, significant levels of Mercury were detected in all 3 fish species, especially in Largemouth Bass.  The bottom-feeding Brown Bullhead had the lowest average mercury concentration at 0.14 mg/kg (same as parts per million); omnivorous Yellow Perch had an average mercury level of 0.31 mg/kg; and predaceous Largemouth Bass had a mean of 0.40 mg/kg.  The State of Massachusetts has issued advisory warnings to anglers and esp. pregnant women who eat freshwater fish caught in the state.   To give the reader a good comparative idea of the significance of these numbers, note the following mercury levels in fish species for which the FDA and HHS (Health and Human Services) has issued warnings to pregnant women avoid eating: Mackerel King, mercury mean of 0.73 ppm (same as mg/kg), Swordfish—0.97 ppm, and canned Albacore Tuna 0.35 ppm.  The FDA issued a warning to pregnant women to limit their intake of Albacore Tuna—it’s average mercury level of 0.35 ppm is lower than the mean mercury level of 0.40 ppm in Largemouth Bass in least-impacted Massachusetts water.

C.      While the mercury levels reported above are those contained in muscle of 3 fish species in Mass. Waters, and the warnings are to humans , it is reasonable to suspect that the mercury, which causes brain damage in humans, probably has an ill effect on the health and reproductive capability of Alewives and other fish native to the Alewife waters.

D.       Measurements of sediment metal concentrations from the lakes studied above by the DEP for the same report also found Arsenic, Selenium, Cadmium, and Lead in the lakes, despite the fact that there were no know point sources—such as landfills-- near the lakes.  Eight of the 24 Lakes studied had lead levels above 100 mg per liter of water.  While we know that lead is detrimental to the mental and physical health of humans, we are not aware of studies of the effect on fish.  However, it is a reasonable hypothesis that arsenic and lead, among other metals, may have negative effects on the health, survival, and reproductive capability of Alewives and other fish native to Alewife water.

E.         The Empact monitoring results as forwarded to us by Julie Horowitz reveals levels of nitrates and  phosphorus in the Alewife Brook.  It may be that nitrates and phosphorus have a negative effect on Alewife health and reproductive ability.

      X.    Empact  and other monitoring results for bacteria such as fecal coliform counts and E Coli counts have shown that the number of colony forming units has sometimes exceeded 1000 per 100 ml of water.  These levels are known to be hazardous to humans.  It is reasonable to hypothesize that high bacteria levels may be hazardous to the health and reproductive ability of Alewives and other native fish.

C.     Proposals for Research, Monitoring, and Improvements to the Alewife Brook, Little River, and Little Pond.

     Here are some proposals for work to be done:

1.      Monitoring:

a.       water depths in the Alewife Brook, Little River, and perhaps the Mystic River should be measured on a monthly basis from April to October, when the Alewife run ends.

b.      Water temperature should be measured at points along the Alewife Brook, Little River and Little Pond, and Mystic River should be measured on a monthly or bi-weekly basis from April to October.

c.        Flow rate should be estimated or measured for these water bodies on a monthly or bi-weekly basis for these months.

d.      Suspended clay levels in these water bodies should be monitored.

e.       Silt measurements should be made. Turbidity should be measured monthly, using a Secchi disk or other technical means.

f.         Inquiries of dam operations and observations of them should be made.

g.       Inquiries to the city or town governments of Cambridge, Belmont, and Arlington, as well as to the DCR should be made to determine whether pesticides or other chemicals have been deposited on the Alewife water.

h.        Measurements of Mercury, Arsenic, Lead, Cadmium, and other metals which may be present should be made on a monthly or bi-monthly basis in the Alewife water bodies.

i.         Bacterial, nitrate, and phosporus measurements should continue in the Alewife Brook near the mouth and should be made in the Little Pond and Little River.

2.       Research to be done: Research on the effect of all of the parameters mentioned above as possible causes of the decline of the Alewife runs and on the effect on fish health and reproductive ability from the many pollutants in the Alewife water should be done.   This would include (1) literature searches, (2) interviews with experts on Massachusetts water bodies and fish, and (3) analysis of information so gained by us..

3.      Some Possible Improvements would include: 1. dredging the Alewife Brook and Little River (not immediately likely to be funded) to increase water depth; 2. cleaning up the water of any or all pollutants, including metals, bacteria, pesticides, motor oil, among others. The proposed use of the Alewife Reservation land as a detention basin as well as the completion of work begun by the city of Cambridge to separate storm and sewer pipes are relevant to this; 3. increasing the Dissolved Oxygen level, the means of which will be studied.

4.      Grant Proposals to be done: a Grant proposal to FishAmerica.org and to one or more of the following organizations for money to do research and improvements—Mass. DEP, Mass. Dept. of Marine Fisheries, Mass. Dept. of Conservation and Recreation, Mass. Dept. of Fisheries, Wildlife, and Environmental Law Enforcement.   The current plan is that a proposal will be submitted by Sanders and Chang as members of Friends of Alewife. 

                               This analysis by S. Sanders and R. Chang, preliminarily done as of October 3, 2004. .