Allan+Hayes

Allan Hayes

//**Will tidal water height affect the species of birds that frequent a cove in Maine?**//

__Introduction__ For years I have loved watching osprey, as many as six to ten at a time, circle over a cove in Maine then dive from 50 feet up creating a splash that can be seen and heard two hundred yards away. Sometimes they fly away with a fish in their talons and most of the times they leave empty clawed. They leave as the water empties the cove leaving a watery, muddy bottom with tasty treats for gulls and shore birds. When the water returns, so do the osprey. I wonder if my casual observations are accurate, consistent, and predictable. Is there a certain water height that is good for the osprey to catch their small fish? Will osprey come only when the water is a specific depth? Will gulls and/or shorebirds come at the same time as osprey? Perhaps the birds will come more in the morning or late afternoon when other birds feed than in midday? While it is fun to watch the other bird activity in this cove habitat, I will work to keep my observations of eagles, kingfishers, and others that I may not recognize separate from my osprey and gull recordings.

__Hypothesis__ As the tide waters go down more birds will appear in a tidal cove in Maine.

__Materials__ Binoculars: Nikon 8x40 Action EX Observation sheet including - Actual low and high tide hour and minute recordings for every day - ½ hour intervals 3hours before and 3hours after the high or low tides during daylight - Space for observations next to the time interval - Open space at the bottom of the page for questions that develop iPad __Method__ - Observe cove for a minimum of six 5 – 10 minute intervals each day - Record sightings on Observation page - Be sure that after five days there are at least two notations in each of the time intervals
 * Use iPad camera to take photos of
 * the cove at each ½ hour increment level
 * birds that I am recording
 * Use Google Maps to pinpoint location of bird sightings
 * Use Flickr to store and label my photos
 * Find a way to graphically show the tide heights on the different days
 * Record daily findings on eBird

Photographs Low Tide, Gulls One Hour After Low Tide, High Above: 2 Osprey Yellow Legs and Willets after low tide
 * __ Data __**
 * __ Analysis __**

Based on a total of 65 observations over a thirteen day period it looks like the number of birds in a tidal cove does increase as the height of the tide water goes down. In fact there are no birds in the cove at high tide. The range of the height of the water was almost 0' at Low to 10' at HIgh Tide. Interestingly, the bird activity differs by species and time of day. Gulls come in when there is practically no water in the cove, and ospreys arrive in very small numbers when the water has covered the bottom. Quite surprisingly, it looks like there are more gulls just after low tide than before high tide, and it looks like more gulls come in during the morning low tides than in the afternoon low tides. Incidentally, the cove was visited by Yellowlegs, Cormorants, a Kingfisher and some Eagles, but not with regularity to warrant daily recordings. Perhaps the reason we see the Yellowlegs and Willets infrequently is because they are stopping on their southern migration.

My data supported my hypothesis that the number of birds in a cove will increase as the tide water decreases, and as the water level goes up the number of birds goes down.
 * __ Conclusion __**

I wonder: - Where do the birds go when they leave the cove? - The gulls appear to be herring gulls. With more powerful optics, I wonder if I can determine if there are other types of gulls? - What are the ospreys eating in the cove? I have watched them diving for small fish, and then flying away with one in their talons. I have counted as many as 20 small fish jumping in a one minute period when the water height was around one foot. What type of fish are these? Are the osprey taking them to their nest or where do they eat their prey? - What are the gulls pulling out of the muddy bottom of the cove?
 * __ Next steps __**