Riparian Zone Retreat:Great Blue Heron

Connor MaustBiology I

Pd. 4

Niche of the Great Blue Heron

The Great Blue Heron can be found during the spring and summer through most of Central and North America.Great blue herons always live near sources of water, including rivers, lake edges, marshes, saltwater seacoasts, and swamps. They usually nest in trees or bushes that stand near water, breeding at elevations of up to 1,500 m. They tend to avoid marine habitats along the east coast and instead live inland.Also, the Heron breeds and lives in the temperate zone which covers our location of Ligonier, PA. The temperature ranges that they can withstand, range from 23.5 degrees to 60 degrees Fahrenheit. The Heron’s also feed on fish, crayfish, salamanders, frogs and other organisms in the lake area.

Blue Herons

Niche of the Great Blue HeronDuring the reproduction cycle, the Heron has one mate per breeding session. Also, the females lay between 2 and 7 pale blue eggs. Birds that live further North tend to lay more eggs than the females in the South. Both of the parents keep the eggs warm during the incubation period.After two months, the chicks are able to fledge and live on their own and become sexually mature at twenty-two months.

Food Chain of Great Blue Heron

Producer

Autotroph

Primary Consumer

Carnivore

Secondary Consumer

Carnivore

Tertiary Consumer

Carnivore

Plant

Frog Great B

lue

Heron

Raven

Food Web Associated with the Great Blue Heron

Producer Carnivore

Carnivore

Producer Omnivore Carnivore

Carnivore

Herbivore

Stream Quality Data and Analysis

0

20

40

60

80

100

120

140

No. oforganisms

Class IClass IIClass III

• The stream condition of Powder mill run is excellent according to the graph because of the number and variety of organisms found in Class I

• Since there is such an abundance and variety of organisms in Class I (126), compared to the (49) in Class II and (0) in Class III, the stream is healthy because organisms in Class I are intolerant to pollution.

• The Great Blue Heron feeds on most creek and lake critters like salamanders, crayfish, fish, frogs and other organisms, so it is great for the Heron to have such a variety and abundance of prey to eat.

Water Testing Data and Analysis

020406080

100120140

StreamMarshMine

• It is healthy for the stream to have a very low level of nitrates. It is healthy for the stream to have a high dissolved oxygen rate so it can supply oxygen to organisms in the dwelling. It is healthy for the pH to range from 6.5 to 7.5. There should also be a low or trace level of phosphates for a healthy stream.

• The ideal range for Nitrates is 0, for dissolved oxygen is around 10, for pH 6.5-7.5 and phosphates should be low to trace amount. The possible ramifications that cause differences in levels of certain aspects could be caused by runoff, burning of fossil fuels, abandoned mine drainage and other factors. Also, the turbidity and temperature are very important factors because the ideal temperature is about 55F in the spring and it will maintain that ideal temperature year round, occasionally rising and falling. Turbidity is the clearness of the water and so a healthy stream will have low turbidity so it enables predators to find their prey. A high turbidity would disarray predator-prey relationships.

• The Great Blue Heron would survive exceptionally well in the Powder mill stream. It would have many organisms to feed on and a great suitable habitat to dwell in. The Heron, however, would not survive well in the AMD area because of the acidity and little organisms that the Heron could feed off of. Same with the marsh, because of all the nitrates and runoff that could poison and kill the Heron would result in the extinction of Herons in that area and also their migration to new feeding grounds

Positive and Negative Factors

• Factors that positively effect the ecosystem are the variety of pollution intolerant organisms that dwell in that riparian zone. Also, the cooler temperature of the water, the low level of nitrates, the higher rate of dissolved oxygen, the neutral level of pH, the low/trace phosphate level and the clear turbidity of the stream are all positive factors that help thrive and sustain a stable riparian ecosystem. Negative factors like AMD, waste deposits, runoff, the burning of fossil fuels, leaching of fertilizers invoke toxins to organisms in the stream which then will eventually kill them and leave nothing for the Heron to eat or live off of. We should conserve the riparian zones by limiting all of these negative factors and restrict them from affecting the riparian zone. The negative factors could very well kill of the Great Blue Herons in western PA, because they are very dependent on a clean and healthy stream full of organisms to feed on.

The Great Blue Heron would survive exceptionally well in the Powder mill stream. It would have many organisms to feed on and a great suitable habitat to dwell in. The Heron, however, would not survive well in the AMD area because of the acidity and little organisms that the Heron could feed off of. With the marsh, it would be livable compared to the AMD but not an ideal habitat because of all the nitrates and runoff that could poison and kill the Heron. It would also not be provided with a depth and variety of organisms to feed on.

River choked by algae

Conclusion

• I learned how little things can have such a huge effect on how other organisms live and how it effects the riparian zone.

• I found it very interesting how it is possible to easily calculate and determine the health of the stream by using somewhat primitive and inexpensive tools.

• I am interested in researching the topic of how the population of one species is effected from one riparian zone.

Works Cited

• http://en.wikipedia.org/wiki/Eutrophication(online encyclopedia)• http://www.jswconline.org/content/40/1/87.e

xtract(online periodical)• http://

animaldiversity.ummz.umich.edu/site/accounts/information/Ardea_herodias.html

(website)