Jeff+Manker

Jeff Manker East vs. West BirdSleuth Investigation

__**Introduction**__

For years I have had a hummingbird feeder on my back deck and have enjoyed numerous hours of watching the hummers feed and fight. Recently my wife suggested that we also get a seed feeder to attract other birds. Because I am now taking the Birdsleuth summer class I thought I could use the decision of where to place the feeder as part of my investigation.

I knew I wanted the feeder on the back deck where we could see the birds from inside the house, but had to decide which end (East or West) of the deck to place it on. The deck faces due South. For the purposes of the experiment I will temporarily place feeders at both the East and West ends (independent variable). The feeders will be identical, hung in the same manner and will hold the same amounts and type of food (control). They will be suspended on poles out away from the deck railing and over the orchard below.

The East end of the deck is very close to both a large apple tree and a large native shrub that are at and above the height of the deck railing. Both are within a meter of the feeder. I think that the birds will prefer this feeder because there is a very active Cooper’s Hawk that has been hunting our orchard (just below the deck) for several weeks now. I believe they will favor this feeder because it allows them to feed while also being close to cover and possible escape from the Hawk.

At the West end of the deck, the nearest apple tree is at least 10 meters away and below the level of the railing. Around the corner on this side are some steps coming up from the orchard, some low bushes, a small pond and a tall Hawthorne tree that has foliage 5 meters above and 5 meters away from the deck railing. The feeder at the West end will be much further from potential hiding places and escape from predators. The birds will have a free choice of what feeder to eat from (dependent variable).

Therefore, my hypothesis is that given equal opportunity to feed from identical bird feeders the birds will choose to feed more from the feeder 1 meter from escape routes rather than the feeder 10 meters away from escape routes.

__**Materials and Methods**__

2 tube type seed-dispensing bird feeders 2 poles to mount the feeders on the deck railing Birdseed Measuring cup Field guides Binoculars Field notebook

1. Two identical tube-type feeders will be suspended on poles from the deck railing approximately 2.5 meters from the ground below. 2. One will be at the East end of the deck near foliage. The other at the West end of the deck much further from foliage. 3. The feeders will be filled with identical amounts of seed each day. 4. In the evening, the remaining seed will be emptied from the feeders and measured. 5. The amounts of seed remaining will be recorded. 6. This will be done for five consecutive days.

__**Results and Analysis**__

After seven days only 50 ml of seed was gone from the East feeder while the West feeder had the identical amount that it started with. They both began with 1300 ml. The East feeder had 1250 ml after seven days and the West feeder had 1300 ml after seven days. I made observations every day at different times of day to see if any birds were using the feeders, but never once saw a bird on either feeder. Having never used a seed feeder before I made several key mistakes that I believe affected the non-use of the feeders.
 * 1) Being brand new feeders there were no populations of birds habituated to using them to begin with and thus none effected by the choice of feeding sites.
 * 2) The tube-type feeders I chose did not match the feeding habits of the birds currently populating my orchard.
 * 3) I unthinkingly put them up in what I later recognized as busy flight patterns of the very aggressive hummingbirds that have been using their feeder for weeks. The most possessive and aggressive birds approached and defended the feeder from primarily two directions: one went directly over the East feeder and the other went directly over the West feeder.

__**Discussions**__

After several days of seeing no birds I decided that I would “bait” the feeders by spreading a handful of seed on the railing next to where the feeders were mounted on poles in hope of attracting birds passing by. My reasoning was that with no population already using feeders, they needed some cue to bring them in. They may not have recognized seed in the feeder, but would likely see and recognize seed setting on the railing and then notice the seed so close by in the feeder and utilize that. The handful of seed on the East side disappeared first. Although I never saw a bird taking it, I believe it was fed on when I was not there to see it, as the winds on the day it was out was very slight and I never saw any on the deck or down below in the orchard, which is where it would have landed if it was blown away.

Once they had taken the seed I did some more research on what birds visited feeders in California from the FeederWatch data collected by citizen scientists over the years. I discovered only four of the top twenty species would even use the feeder type I had chosen (American Goldfinch, Lesser Goldfinch, Purple Finch and House Finch). The Goldfinches are rare at my house. I maybe only see them once a year or two. House and Purple Finches are just not around in the Summer. I see them earlier in the Spring and later in the Fall, but not in July. All the other seed eaters on the list are mostly bigger birds that would not fit on the small perches of the feeder or prefer to take the seed from a platform or the ground. I regularly saw Stellar’s Jays, Mourning Doves, Spotted and California Towhees, American Robins, Chestnut-backed Chickadees, Dark-eyed Juncos and an occasional Black-headed Grosbeak. All of these birds would have eaten the seed, just not from the tube from which it was offered. So in a way I sabotaged my own experiment by not doing enough research to start with. I should also mention, by the time the experiment began, I saw very few birds overall and I stopped seeing the Cooper’s Hawk and began hearing and seeing a juvenile Red-tailed Hawk. I really don’t think the hawk any effect on the non-use of the feeders. Maybe the Cooper’s Hawk had driven many of the bird’s away and it moved on to a new feeding area. The weather was very hot that week and that may have caused the birds to feed more in the forest and out of the more exposed and hot orchard.

At the end of the week with no noticeable feeding I spread seed on the deck railing again and without seeing any birds noticed throughout the day that the same pattern unfolded. The seed disappeared faster from the East side than from the West side. It could have been the resident Chipmunk but I have not seen him in over a week.

__**Conclusions**__

My study was really inconclusive due to the errors listed above. However, when I spread seed on the deck railing both times more disappeared faster from the East side (closer to cover) than from the West side (farther from cover). This gives me an indication that I may have been headed in the right direction with my study, I just used the wrong tools.

I also realize that even if they had taken seed from the feeders as I predicted, It would not have known if it was because of the Cooper’s Hawk unless I had witnessed some attempts at predation during the time of the study.


 * __References__**

The Project Feeder Watch: Top 20 Feeder Birds in California (retrieved 17 July 2012) http://www.birds.cornell.edu/pfw/slides/Top20_California_Region_web.pdf

The Cornell Lab of Ornithology: All About Birds - Birding Basics: Attract Birds: Feeding Birds: Where to Put Your Feeder (retrieved 17 July 2012) http://www.allaboutbirds.org/Page.aspx?pid=1182

BestNest.com Bird Feeder Placement (retrieved 17 July 2012) http://www.bestnest.com/bestnest/bird_feeder_placement.asp