Jeff Brennan

Freshwater Ecology

Lake Ontario Case Study

12/4/13

Lake Ontario

Before great acts of glaciation occurred during the last ice age, Lake Ontario as we know

it today was not a lake, but a river. During the last ice age, which occurred in last years of the

Pleistocene epoch, varying factors over different time periods helped shape Lake Ontario in its

modern form.

In the Pleistocene epoch great sheets of ice 6,500 feet high crept down from artic regions

all over the world. It was at this time that the ice sheet crept over the Ontarian River Valley.

When the ice sheet ran over the terrain in this area, deep moraines and drumlins were carved into

the Ontario River Valley, as well as causing erosion on the sides of the valley (Cox, 1979). The

retreat of the ice sheet as well as the encroachment of it had adverse effects on the geology of the

region.

The retreat of the ice sheet during the last

years of the Pleistocene saw the deposition of

massive amounts of sediment of all size classes

throughout the Ontarian River Valley. These

depositions account for the geological features we

see in the region today, such as limestone plains,

sand plains, till moraines, till plains, clay plains, and kame moraines. There is still speculation

today on how exactly the basin for Lake Ontario was formed, with the most widely accepted

theory being from glacial action.

Another theory is that water accumulated in the lake during the recession of the ice sheet

during the Pleistocene epoch. At that time, the glacier retreated enough to uncover the Ontarian

River Valley, but it still covered its natural outlet to the sea, the St. Lawrence River. Since its

natural outlet was dammed, the Ontarian River Valley filled with water, and eventually began to

flow out of modern day Syracuse. When the ice sheet finally receded past the St. Lawrence

River, the earth was compounded so much by the weight of 6,500 feet of ice, that Lake Ontario

formed a bay of the Atlantic Ocean, in conjunction with Lake Champlain.

Due to rebounding of the earth’s crust,

the coastal region eventually rose up out of the

water. When the earth rebounded, it caused

high velocity water throughout the region

from the displacement of such a gigantic

volume of water. These high velocity currents

scoured the sides of the basin, along with the lake

floor (Cox, 1979). Douglas E. Cox argues that the

drumlins and moraines that are featured in the topography of the Lake Ontario floor and the

surrounding region are the result of high velocity currents, and not glacial action. This is due to

drumlin shape indicating that their formation was due to fluid flow and sediment transport.

Cox then goes on to show that the loess hills in eastern Washington were formed by the

fluid flow from massive flooding, resembling the drumlins in shape and size (Cox, 1979).

Sonar Photo of drumlins on the Lake Ontario bed.

Regardless of how Lake Ontario was truly formed, it today is 193 miles long and 53 miles wide,

with an average depth of 283 feet and a maximum depth of 802 feet. 24, 720 square miles of

drainage basin are supplies the waters of Lake Ontario. Lake Ontario is the 14th largest lake in

the world (Manninen, 2012).

The thermal stratification cycle of Lake Ontario was found by making midlake cross-

section measurements of eastward wind stress. The dominant role for lake stratification of Lake

Ontario comes from wind stress. Lake Ontario reaches stratification in the summer when surface

water temperature reaches 4 degrees Celsius. Due to the depth of water, topography of the lake

bottom, topography of the shoreline, the thermal bar is more developed towards the north shore,

the shallow part of the lake. This stratification can be broke from upwelling or down welling

from the strong easterly winds that frequent Lake Ontario (Edsall, 1997).

After glacial action occurred, Lake Ontario’s history went through several more climate

changes, which had adverse effects on its productivity. A case study on the paleo-primary

productivity during of the past 10,000 years was performed in order to better understand the

patterns in the lakes productive history (McFadden et al, 2004). If you can understand the

patterns that the lake goes through, you can map out what the future could potentially hold for

the lake. This is important because a lot of Lake Ontario’s economy is reliant on this primary

productivity, such as sport fishing, recreation, and water quality.

Long sediment piston cores were taken from eastern Lake Ontario from the Rochester

Basin. These cores were up to 5 meters long, and 3 centimeters in diameter, were collected in

plastic liners, divvied up into sections, and then were stored. Total nitrogen, organic carbon, and

their ratios were measured with an elemental analyzer. The content of the two cores contained

mostly gray-brown mud with oxidized clasts in the basal 74cm, while the rest of the core was

made up of brown mud with black laminations from iron and sulfide rich bands forming in times

of low oxygen (McFadden et al, 2004).

In order to determine the age of the sediment, analysis of biogenic carbonate was used

instead of radiocarbon data since organic molecules

from glaciated watersheds can produce radiocarbon

ages that can be thousands of years too old. Once

accurate radiocarbon dates were found, they were

than transcribed to calendar years using the CALIB

4.2 program (McFadden et al, 2004). The age of

the core samples range from 10,000 years ago to

1940 A.D (McFadden et al, 2004).

Carbon to Nitrogen ratios were also determined for the cores. The cores highest ratios

for C:N were obtained from the lower section of the core. The core has an average C:N value of

around 13. When the sediment age is around 5.3 ka, C:N ratios drop to approximately 10. This

decrease in C:N ratios shows a decrease in primary-production at the time, and can be attributed

to the Younger Dryas event, which was a cold period in the region (McFadden et al, 2004).

Biogenic silica was also analyzed from the two cores taken from the Rochester Basin in

Lake Ontario. Analysis of biogenic silica allows for modeling of the diatom levels throughout

the cores history, thus modeling the health of the primary productivity from that time period.

McFadden et al breaks down the percent biogenic silica levels into three separate parts, post

Younger Dryas and Hypsithermal interval, Neoglacial interval, and the historically current

interval (McFadden et al, 2004).

Figure 1

The post Younger Dryas and Hypsithermal interval have percent biogenic silica less than

1%. This trend is attributed to low diatom productivity or dissolution, most likely brought on by

the cold temperature of the time period. The Neoglacial period brings on a slight increase in

biogenic silica, while the historical time period shows a rapid increase in percent biogenic silica

(McFadden et al, 2004).

During the post Younger Dryas period, percent total organic material, percent biogenic

silica, percent carbon, and percent nitrogen were all at a minimum for the time frame studied.

This is a result of the polar jet

moving southward over the northeast

United states, causing a shorter growing

season, limiting primary production.

After this period the Holocene

hypsithermal period came, bringing with

it warm summers caused from increased

insolation from orbital patterns

(McFadden et al, 2004). This obviously brought

about an increase in primary productivity and an increase in percent total organic material,

percent biogenic silica, percent carbon, and percent nitrogen.

In the historical interval, we see some of the most dramatic changes brought upon Lake

Ontario. Due to deforestation in the watersheds of Lake Ontario, sedimentation rates vastly

increased. While time periods such as the Neoglacial had sediment accumulation rates of 18cm

1,000yr-1, the 1850’s experienced sedimentation of around 600cm 1,000 yr-1. Percent carbon,

percent nitrogen and percent total organic material all increased, showing an increase in primary

Figure 2

production. This primary production was brought on by eutrophication from nutrient loading by

disturbances such as deforestation, municipal, industrial, and agricultural sources (McFadden et

al, 2004).

This historically recent eutrophication of Lake Ontario has been studied in The Bay of

Quinte. The Bay of Quinte is one of the largest and most developed areas on Lake Ontario. It

has an area of 87 square miles and lies on the northeastern shore of Lake Ontario. The entire bay

is made up of an inner bay, a middle, and an outer bay. The major water ways that run into the

Bay of Quinte are the Trent River, the Moira River, the Salmon River, and the Napanee River.

Combined, these rivers drain 6,550 square miles of watershed. Trent River has an average cfs

(cubic feet per second) of 3,990,

Moira River has an average cfs of

888, Salmon River has an

average cfs of 357, and the

Napanee River has an average cfs

of 330.

The Bay of Quinte is located on the north eastern shore of Lake Ontario. This area of

Lake Ontario and its tributary rivers are some of the most

highly urbanized and highly industrialized areas in the region. A case study on the nutrient

cycling of The Bay of Quinte was assessed to determine water quality. Water samples were

taken over 26 days, with sampling effort intensified during periods of high flow. Colorimetric

analyses were then made on an automatic analyzer (Johnson et al, 1971).

What the results found were that the Trent River which flows into the Bay of Quinte,

Lake Ontario has a mean concentration of nitrogen of .71 +/- .12 (mg/+/-28.E.), the Moira River

Figure 3

has a mean concentration of Nitrogen of .64 +/- 12(mg/+/-28.E.), the Salmon River has a mean

concentration of .68 +/-.08(mg/+/-28.E.), and the Napanee River has a mean concentration of

nitrogen of .83+/-.1(mg/+/-28.E.). The Trent River has a mean concentration of Phosphorous

of .050+/-.012(mg/+/-28.E.), the Moira River has a mean concentration of Phosphorous of .037

+/-.006(mg/+/-28.E.), the Salmon River has a mean concentration of phosphorous

of .027+/-.006(mg/+/-28.E.), and the Napanee River has a mean concentration of phosphorous of

.043+/-.006(mg/+/-28.E.). From these water samples they were able to extrapolate that the Bay

of Quinte annually receives 112,000 pounds of nitrogen, and 8,400 pounds of phosphorous per

square mile (Johnson et al, 1971).

These massive amounts of nutrient input resulted in huge algal growth in response.

Algae was taken in samples, and amount of algae was measured through the use of a secchi disc.

The inner bay was by far the area with the most algal growth on the Bay of Quinte, with secchi

disc readings of only 1ft in depth. This means that the water was so thick with algae in this area

the visible distance you can see into the water is 1ft. This compared to the 8ft secchi disc

readings in the middle bay, and the 11ft secchi disc readings in Lake Ontario off the bay mouth

show how much trouble the inner bay really is (Johnson et al, 1971). Size of the algal blooms

decrease to the right of the table. Big Bay is in the inner bay, Glenora is in the middle bay,

Conway is in the outer bay, and the Lake Ontario was taken at the mouth of the bay. The Big

Bay’s dominant form of algae are blue-green algae and are present at an average of 2,910 asu/ml,

with asu being the areal standard unit, which is 400 microns ^2. Diatoms are the second largest

group in the Big Bay, and are present at an average of 1,330 asu/ml. This compared to the Lake

Ontario numbers where the average blue-green algae present is 50 asu/ml, and the average

diatoms present are 200 asu/ml (Johnson et al, 1971). The inner bay is worse than any other areas

of the Bay of Quinte because it is the closest in proximity to the heads waters that are flowing

into the bay, bringing with it all the dumped waste from agriculture, industry, and municipalities.

Big Bay

Glenora

Conway

Lake Ontario

Mean

Mean % Max Mean

Mean % Max Mean

Mean % Max

Mean

Mean % Max

Blue-greens

2,910 65.4

30,900 670

35.30

3,200 270 22.6

2000 50 18.2 260

Diatoms

1,330 29.9

4,400 1,120 58.9

2,700 850 71

2,300 200 76

1,300

Others 210 4.71,60

0 120 5.8 550 80 6.4 510 20 5.8 70

Total4,45

0 10031,8

00 1,910 1004,500 1,200 100

2,500 270 100

1,630

Figure 4

With all of these wastes being dumped into Lake Ontario, drinkability of its water has

come into question. Actinomycetes are a filamentous form of bacteria that are known for

causing an earthy smell and taste in water. This taste and odor derives from the bacteria’s

production of geosmin and 2-methyl-isoborneol. However, the actual cause for this taste and

odor in the drinking water has yet to be determined. A case study was developed in order to test

if odor and taste production is species specific, if some habitats facilitate the growth of

actinomycetes, or if flow inputs are the source of actinomycetes. Three separate samplings of

water occurred throughout the year.

The first was in early September and its data was used to determine the abundance and

taxonomy of actinomycetes from the surface and bottom. These water samples were taken both

offshore and at river or stream inputs. The second set of water samples were taken in the middle

of October. The sites had the same kind of variation as the first, in that there was both offshore

sampling and inshore sampling at the mouths of rivers and streams. The third series of water

samples were taken in the middle of November in the St. Lawrence River. Here triplicate

mussels and macrophyte samples were taken from the littoral zone from 1 square meter plastic

grids divided into nine sections.

What the results found were that actinomycetes were found at all sites, and were most

abundant in suspended sediment, periphyton, macrophytes, and mussels. The highest amounts of

were found at the mouths of rivers in suspended sediment. This means that the majority of

actinomycetes in the water column are being washed from terrestrial habitats into streams and

tributaries that flow into Lake Ontario.

To test how much geosmin and 2-

methyl-isoborneol, 41 actinomycetes were

isolated in a culture. Of the 41

actinomycetes, 22 were of the species

Streptomyces, and the other 19 were of

other actinomycete genera. In

Streptomycetes, 23% produced only

geosmin, 14% produced only 2-methyl-

isoborneol, and 41% produced both

geosmin and 2-methyl-isoborneol. 23% of

Streptomycetes produced neither geosmin nor 2-

methyl-isoborneol. Among the other actinomycetes, 11 % produced only geosmin, 37%

produced both, and 42% produced neither.

Lake Ontario has seen a multitude of invasive species take hold in its waters. Usually,

foreign species are introduced to Lake Ontario through international ships who unload their

Figure 5

contaminated ballast water into its waters. This dumping has accounted for approximately 70%

of faunal non-indigenous species.

In a case study taking place in Lake Ontario Canada, macro invertebrate communities

were assessed pre and post invasion of a mussel of the genus Driessena. The mussel’s invasion

into the Lake Ontario waters had both positive and negative effects on the lake’s organisms.

When Driessena moved in, it gave benthic grazers a food source that it could rely on, effectively

increasing the growth rate of benthic grazers in the area. Driessena is also the dominant filter

feeder in Lake Ontario, out-competing most other filter feeders. This out competing comes from

the Driessenas more effective ability at filtering the water for food, eliminating it for others.

Driessena also smothers organisms such as unionids (Haynes, 2005).

Driessena further outcompetes other species by eliminating habitat for other organisms to

live on. The productivity of other organisms decreased as a result of this, since they were

effectively eliminated from the water, and have less nutrients and food sources to rely on for life.

Driessena requires sphaeriids greater than 1mm in size to settle on, and by 1997 sphaeriids at a

depth of 10m had vanished (Haynes, 2005). This case study suggests that caddisflies in the wave

zone of eastern Lake Erie, and filter-feeding chironomids in deep water in eastern Lake Erie have

both been displaced by Driessena.

In order to test that Driessena was in fact the organism to blame for the decrease in

macroinvertebrates, a study using a natural cobble site and an artificial reef site were studied pre

and post Driessena invasion. What the study found was in cobble sites, Driessena comprised

40% of the abundance of macroinvertebrates, and in artificial reef sights Driessena comprised

60% of the abundance of macroinvertebrates, see Figure 6(Haynes, 2005).

Lake Ontario’s fish populations also have been hindered due to invasion of non-

indigenous species. The decrease in fish stocks in Lake Ontario in the early 1940’s and through

the 1960’s can be partially attested to an invasion of sea lampreys. Sea lampreys began making

their way into the Lake Ontario and other Great Lakes from the St. Lawrence River, which is an

outlet to the Atlantic Ocean. These sea lampreys attach themselves to mature large fish, and

suck the blood out of them for nutrients. Eventually the large fish would be unable to gather

enough resources to allow for both it and the sea lamprey, so then it dies (Christie, 1974).

This however is not the largest factor in the depletion of large fish stocks in Lake Ontario

in the 1940’s through the 1960’s. As a result of “The Tragedy of the Commons,” most of Lake

Ontario’s commercially valuable fish species were fished into the ground.

Figure 6

The tragedy of the commons is an economic theory stating that the depletion of a shared

resource by individuals, acting independently and rationally according to each one’s self-interest,

despite their understanding that depleting the common resource is contrary to the group’s long

term best interest.

This tragedy of the commons trend started with the colonization of the Great Lakes in the

early 1800’s, and fishing was one of the top commerce at the time in the area. In this case study,

fish catches from 1940 to 1972 were analyzed for trends. In 1940, Lake Ontario recorded

approximately 90 metric tons of commercial yield for lake trout, see Figure 7. In 1957 the

commercial yield for lake trout was 0

metric tons. In 1940, Lake Ontario

recorded approximately 240 metric

tons of commercial yield for

whitefish. In 1972 the commercial

yield for whitefish was 0 metric tons.

In 1940, Lake Ontario recorded approximately 750

metric tons of commercial yield for deep water ciscoes. In 1959 the commercial yield for deep

water ciscoes was 0 metric tons. In 1940, Lake Ontario recorded approximately 90 metric tons

of commercial yield for herring. In 1968 the commercial yield for herring was 0 metric tons

(Christie, 1974).

As you can see the tragedy of the commons really took its toll on the large fish populations of

Lake Ontario. More specifically, the fish populations with a commercial value.

Even though these figures are daunting, they are not 100% accurate. Firstly, just because

a fish species have 0 recorded commercial yield does not mean that there are 0 of that fish

Figure 7

species in the lake. It just means that they stopped catching them, most likely because it was no

longer economically viable to go after a collapsed fish stock. Also early records for fish catch

were incomplete or varying in consistency during the early years, making it hard to get accurate

data (Christie, 1974).

Commercial fishermen were also not required to report fishing effort. Long term

changes in fish population are harder to determine from catch alone, without fishing effort. This

is because you could spend all day trying to catch a boatload of fish, if that targeted fish species

is poor shape, or you could catch a boatload of fish in 1 hour if the fish is in great shape. This is

why it is difficult to determine fish stock health from catch alone (Christie, 1974).

Luckily today, improved fishery management techniques have allowed for a rebound in

most fish species in Lake Ontario. Some of these practices include a no catch policy on sturgeon

on the Great Lakes and the surrounding tributaries. The sturgeon was almost wiped out of Lake

Ontario when they were overfished for their caviar and oils. The New York government has also

gone as far to post warning signs at popular fishing sights to return caught sturgeon to the stream

or lake where they were caught. Another good fishery management technique was applied to the

muskellunge ("Fisheries management ," 2013).

In 2005 and 2006 the virus Hemmorrhagic septicemia killed half of the mature

muskellunge population. The Ontario Fishery Management division then increased the

minimum size limit for muskellunge to 54 inches ("Fisheries management ," 2013). Recreational

fishermen also advocate on behalf of fishery management, especially in the case of the

muskellunge. Fishermen have made keeping a muskellunge a taboo, due to its rarity and long

life cycle. They also encourage safe release techniques, where you hold on to the muskellunge’s

tail, and hold it upright until it is able to swim away on its own accord.

By understanding Lake Ontario’s past, we are better able to shape its future. The

knowledge of the origin of Lake Ontario, along with its trends of productivity are necessary for

modern day comparisons for remediation strategies. Lake Ontario needs to be managed for

invasive species, nutrient control, and over-fishing if it is to stay a healthy and sustainable

ecosystem.

Sources:

Mullin, H., Patterson, W. P., Anderson , W. T., & McFadden, M. A. (2004). Paleoproductivity of

eastern lake ontario over the past 10,000 years.American Society of Limnology and

Oceanography, 49(5), 1570-1581. Retrieved from

Http://www.jstor.org.ezproxy.stockton.edu:2048/stable/pdfplus/3597427.pdf?acceptTC=t

rue

Cox, D. (1979). Drumlins and diluvial currents. Creation Research Society Quarterly, 16(3),

154-162. Retrieved from http://www.sentex.net/~tcc/drumlin1.html

Manninen, C. (2012). Lake Ontario facts and figures. Great Lakes information network,

Retrieved from http://www.great-l lakes.net/lakes/ref/ontfact.html

Johnson, M. G., & Owen, G. E. (1971). Nutrients and nutrient budgets in the bay of quinte, lake

ontario.Water Environment Federation, 43, 836-853. Retrieved from

http://www.jstor.org/stable/pdfplus/25037390.pdf?&acceptTC=true&jpdConfirm=true

Christie, W. J. (1974). Changes in the fish species composition in the great lakes. Ontario

Ministry of Natural Resources, 31, 827-854. Retrieved from

http://fishwild.vt.edu/fiw4614/23 Christie 1974.pdf

Edsall, T. (1997). Nearshore waters of the great lakes.State of the Lakes Ecosystem Conference,

Retrieved from

http://www.epa.gov/solec/archive/1996/Nearshore_Waters_of_the_Great_Lakes.pdf

Haynes, J. M. (2005). Benthic macroinvertebrate communities in southwestern lake ontario

following invasion of dreissena and echinogammarus: 1983 to 2000 . Journal of the North

American Benthological Society, 24, 148-167. Retrieved from

http://www.jstor.org.ezproxy.stockton.edu:2048/stable/pdfplus/4095705.pdf?acceptTC=tr

ue&acceptTC=true&jpdConfirm=true

Fisheries management zone 20 (lake ontario). (2013). Retrieved from

http://www.mnr.gov.on.ca/stdprodconsume/groups/lr/@mnr/@letsfish/documents/factsheet/

stdprod_101639.pdf