Snowy plover (Charadrius alexandrinus nivosu) Wintering habitat vs non-wintering habitat, and community awareness




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Snowy plover (Charadrius alexandrinus nivosu) - Wintering habitat vs. non-wintering habitat, and community awareness



Submitted by:
Caylen Clark


Haley Priest

Junko Yoshimaru

Sarah Tomscha

Aja Neahring

Jane Goodall Environmental Middle School

June 1, 2005

Submitted to:

U.S. Fish and Wildlife Service

Oregon Coast National Wildlife Refuge Complex

2127 SE OSU Drive

Newport, OR 97365

Introduction

The Snowy Plover’s (Charadrius alexandrinus nivosu) numbers were dramatically decreasing as their habitat disappeared. Humans walking on the beach, dogs, and kites were also interfering with their lifestyle. The Snowy Plover is listed as threatened in Oregon and even endangered in some states. Many people don’t realize this or the fact that what they could be doing might cause the Snowy Plover’s to become extinct. Their extinction could cause a trophic cascade. The numbers of the insects that they feed would go up, eventually affecting the whole food chain.

Snowy Plovers typically weigh 34-58 grams and are 15-17 centimeters in length. Their feathers are a pale grey-brown above, and white below. They have a dark collar and dark lateral breast patches although when breeding males tend to have black markings on the head and breast. Females tend to have one or more of these markings during breeding season as well. During non-breeding season you cannot see the difference in gender for they will lose their breeding plumage. Most Snowy Plover’s live to be 3 but can live up to 15 years.

Snowy Plover’s need flat areas with sandy or saline substrates. Nests consist of a shallow scrape or depression lined with beach debris such as small pebbles, shells, plants, and mud chips. Nest lining will increase as incubation progresses. Driftwood and kelp provide protection from predators so the chicks can hide. Nest are usually 100 meters away from the ocean but can be several 100 meters away if there is no vegetation barrier because the chicks need to be able to reach water easily. Many Snowy Plover’s, return to the same place to nest.

To know how to solve any problem you must first understand why it became an issue. Snowy Plover’s have many factors working against them. One of which is the sand mined in some beaches. This can cause erosion and loss of breeding and wintering habitat. Heavy machinery used to mine the sand can disturb incubating plover’s and even destroy nest or chicks. Mining sand can result in the loss of invertebrates and kelp that plover’s use for forging

European Beach grass is one of the prime reasons of habitat loss for coastal breeding Snowy Plover’s. This introduced beach grass takes over the beach, making the diversity of native dune plant species much smaller. European Beach grass also binds the sand much tighter because it has longer roots than the American dune grass. This causes larger dunes, which are bad news for snowy plover, making it harder to reach the wrack line.

Snowy Plover’s were listed as threatened so a recovery plan was set up. Actions to ensure a recovery in their numbers include protection, enhancement, and restoration of all habitats vital to their recovery. Monitoring, research and public outreach is being done as well. USF and WS were even trying to close down parts or whole beaches. There are also habitat restoration areas along the coast and roped off breeding sites set up in March.

With so many reasons to save the Snowy Plover it is hard to imagine why there would be to different sides but as in any problem, there is. People enjoy playing on the beach and many other leisure activities including riding ATV’s and walking their dogs. Unfortunately most of these activities threaten the existence of Snowy Plovers.

Our project will be located mostly in Florence although Snowy Plover’s are located not only in Oregon but in Washington and California beaches as well. Our group’s job is to compare beaches where Snowy Plover’s winter to ones where they don’t. We will be comparing habitat variables including measuring driftwood, vegetation, the wrack, and slope of the beach. Our group also plans to survey people on their knowledge of Snowy Plovers in spring.

The questions we are trying to answer is: Why do Snowy Plover’s nest in certain places in the winter? How much do people actually know about Snowy Plover’s and how can we help raise awareness? I hope we can contribute to the effort to save their numbers by creating awareness to the human community by handing out brochures and surveying. We will also gather good data about their wintering habitats so we know what we can do to make a beneficial habitat.

I believe that we will find a difference in the places they prefer to winter at and the places that they don’t or have stopped wintering at. I think that they need a habitat with a lot of driftwood and vegetation but not as much European dune grass. I also think that it is best if they have a flat beach but a beach with many small dunes would be better than one large dune. I don’t believe many of the people we interview will know much about Snowy Plover’s or have seen the signs about them.
Methods

We conducted our research on November 12 and 13, 2004, and February 13 and 14, 2005 at Florence, Oregon. Over a period of two days we stopped at 3 beaches and preformed the same procedure at each beach .We collected data once at Baker and Suislaw North Jetty. We also went to Dunes overlook where we recorded information twice, on different days. We picked a random number from a random number table and walked that many meter from the access point for each beach. Once at the random location we set up one stake at the fore dune. Next we measured 25 meters down to toward the ocean and put another stake there. We then, put up nine more sets of these stakes. Each set was 50 meters apart for a total of 20 stakes. At the fore dune we marked the stakes location on the GSP. We also measured the slope of the stake at the fore dune to the stake closer to the ocean for each set. We calculated the slope with an Abney level. The third thing we measured was the driftwood and vegetation. We did this by walking from the foredune towards the 25-meter mark and measured the vegetation and driftwood in a four meter wide transect. We made meter squares on each side of the line and estimated the percent cover of the vegetation and driftwood and marked the data on our data sheets. We measured the driftwood in each square by drawing it in and also recording if it was extra small, small, medium, or large. The fourth and final thing we measured was the wrack. We estimated the wrack the same way and we used the same kind of meter squares. The only thing different was we decided where the wrack line and set up the square there and we estimated the percentages of wrack in each square. When we were all done doing that, we wrote down information on the beach and dunes. Such as if the beach was relatively flat or how many hummocks there were. We also noted how many people or animals we saw. We recorded anything that we believed would be useful to know.



For our surveys, we split up into two different groups at each of our locations. We went to Suislaw North Jetty, Siltcoos Spit, and the town of Florence. Earlier our group had come up with a survey that we then asked everyone we could.

Results
As you can see in Graph 1, Snowy Plovers prefer to winter at beaches with a smaller slope such as Suislaw N Jetty and Baker beach. They do not winter at Dune overlook however, where the slope is much higher.
Graph 2 shows the places that they winter at, Baker beach and Suislaw N Jetty, have no or very little vegetation. The first trip to Dune Overlook we measured quite a bit vegetation, but the second time we went there was none. These graphs show no correlation. You can’t tell whether Plovers prefer to winter at places with no vegetation or with an abundance of vegetation.
Graph 3 shows the places they winter at, Baker beach and Suislaw N Jetty, both have large amounts of driftwood, or larger amounts then were found at Dune Overlook. You can find out by looking at our data that Snowy Plovers prefer to winter at places with a lot of driftwood than at beaches with smaller amounts.
Graph 4 tells us that the average number of meters squares that contain wrack on each of the transects. As you can see the places that they winter at, Baker and Suislaw N Jetty have a large difference in the amounts of wrack found. At Dunes Overlook, where the Plover don’t winter, there is also a big difference. The amount of wrack on average, however, tends to be more at the Dunes Overlook sites opposed to the wrack at the places they winter at.
Graph 5 tell us the answers to the first question “Do you know what a Snowy Plover is?” We separated the graphs two ways. The first was splitting it into yes and no answer for each beach. The second way we split it was the total yes’s and the total no’s. The yes’s are all shades of red, or warm colors while the no’s at each place are all blue, or cold colors. About 60% of the people we asked had heard of a snowy plover before.
Graph 6 shows us the answers to the question “Do you believe saving the snowy plover is important. Once again, we split the graph the same way as graph five. 94% of the people we asked thought it was important and 6% said it didn’t matter if the snowy plover went extinct.



Graph 1. This data was collected at five different sections of beach along the Oregon Coast. The warm colors represent the sections where the Snowy Plover’s do not winter and the cool colors represent the sections where the Snowy Plovers winter. The slope was measured from the fore dune to 25 meters towards the ocean.




Graph 2. This data was collected at five different sections of beach along the Oregon Coast. The warm colors represent the sections where the Snowy Plover’s do not winter and the cool colors represent the sections where the Snowy Plovers winter. We walked a 25 meter transect and estimated the percent of vegetation cover in each meter square throughout the 4 meter wide transect. This data represent the average amount of vegetation per Meter Square.




Graph 3. This data was collected at five different sections of beach along the Oregon Coast. The warm colors represent the sections where the Snowy Plover’s do not winter and the cool colors represent the sections where the Snowy Plovers winter. The driftwood data was collected by recording all the driftwood in each 25 meter transect and then labeling it either extra small, small, medium, large, or extra large.


Graph 4. This data was collected at five different sections of beach along the Oregon Coast. The warm colors represent the sections where the Snowy Plover’s do not winter and the cool colors represent the sections where the Snowy Plovers winter. The wrack was measured by making meter squares on the 25-meter transect that was 4 meters wide. We then found the average amount of boxes where wrack was found per transect.

Graph 5. This survey was taken at 3 different areas at or near Florence, Oregon. As you can see many people knew about the Snowy Plover but a lot of people didn’t. Most of the people who didn’t either didn’t live in the area or had never seen the signs on them.
Graph 6. This data was taken at three locations in or near Florence, Oregon. As you can see most people were in favor of the idea to say the snowy plover.

Discussion

Our data showed that the beaches the Snowy Plover’s don’t winter at, Dune overlook, tended to have more wrack than the beaches they do winter at, Baker Beach and Suislaw N Jetty. Although Suislaw N Jetty did have more wrack that one of the times we recorded at Dunes Overlook, the places the don’t winter at, generally, have less wrack than the non-wintering beaches. The non-wintering beaches still had plenty of wrack. We first decided to include this piece of information in our data because we believe the Snowy Plover’s would need the wrack in order to receive their food.


This data could be dramatically different however if we had recorded at different times of the day, they weather would have been different, or at different beaches. It would be hard to make any big conclusions though, because we only took samples five times. These results don’t really help our research because the graph shows no correlation. We can’t say that Snowy Plover’s need more wrack in order to winter at Baker Beach or Suislaw N Jetty.
For driftwood we noticed that the places they winter have a lot of driftwood compared to the beaches where they don’t winter. The beaches also tended to have larger driftwood. These results matched with my predictions because I thought the Snowy Plover’s would need a lot of driftwood at the places they wintered at. I thought this because in the winter’s harsh wind and rain the small Plover’s will need something to hide behind. As it turned out they did. This data will help our research because now we will know we that they need driftwood in order to winter.
Our slope data showed that the beaches where the snowy plover’s winter were, flatter than the beaches were they chose not to winter. My prediction was the same as the data showed. I know that the Snowy Plover’s need a flat beach because they have small legs. If you have small legs it would take more energy on a steep beach, to get back and forth from home to ocean. They must go to and from the ocean frequently to get food, and they need the energy to run.
Our research showed that there was no correlation between the amounts of vegetation at wintering and non-wintering beaches. There wasn’t much vegetation at any of the sites we collected data at besides a section of Dune Overlook. The reason this site had vegetation was because it was a habitat restoration area where they had bulldozed all the European beach grass. This caused the beach to be flat, and lead to a better habitat for native vegetation. We can’t tell if the Snowy Plover’s need more vegetation in the habitat they winter at or not. The Plover’s don’t winter at beaches with much vegetation but maybe that is only because there aren’t any beaches with much vegetation. It will be interesting to see if the Snowy Plover’s winter at Dune’s Overlook, with more vegetation, in the future. Since this is just a recent habitat restoration area the effects haven’t started yet.
I believe if our group had had more time to collect data we have found better results. The more beaches you collect data at the more answers you will get and the closer you will be to understanding wintering habitat. It also would have been helpful if we had the same people collecting the data on wrack, driftwood, slope and vegetation each time. We chose to shift jobs so we would all have the experience of finding each thing and collecting different types of research. This made the human error level will increase, especially on estimating vegetation, driftwood and wrack cover. Everyone estimates and interprets things differently.
I think that we were able to answer our research question. We asked at the start of our project what the difference was between the places the Snowy Plover’s winter at and the places they chose not to. According to our data we found out that snowy plover must have driftwood and they also need a smaller slope than some of the beaches are able to offer. I think that it doesn’t seem to matter to the Snowy Plover’s how much wrack or vegetation they have. It doesn’t improve their habitat. However, we found that snowy plover’s must have driftwood and a low slope in order to winter at these beaches. If we could add driftwood and maybe bulldoze down the European beach grass it would improve the habitat, raising their numbers. If we were able to bring back the native vegetation instead of the European beach grass the dunes wouldn’t be as steep. I believe it would be interesting to also study the nesting area of the snowy plover, what they need to nest and how to make a better environment for the chicks. If the chicks are able to live until adults there is a smaller chance they will die. Chicks are much more vulnerable. This would also be able to improve their habitat, raising their numbers.

As we know, the Snowy Plover’s population has been decreasing for years and if it continues this could lead to their extinction. Now we are on the right track. Studying the wintering habitat is only one step in the long process of raising the snowy plovers numbers but it is an important one. You can’t begin to fix something that you don’t know is a problem. Now that we know the issues with the non-wintering beaches we can fix them. That is also why we decided to spread community awareness. The more people know, the more they will do to help. When we all work together, anything becomes possible. I believe one day in the near future snowy plover’s will be abundant on every beach, for everyone to enjoy and observe.

Before we asked the questions I thought that most people’s opinions would be the same but many were not. Out of the 18 questions we asked I thought the two that were the most interesting answers we got were for “what is a snowy plover?” and “do you believe saving the snowy plover is important?” For the first question 59% of the people, at the answer from the sites combined, knew what a snowy plover is. The least people knew about the bird at NJ, with only 9%. At Suislaw 22% did and in Florence 28% did. This was happened most likely because there were more signs in theses areas. 41% of the people we surveyed said they didn’t know what a snowy plover is. This is still a fairly high percentage and it shows us that more signs and other ways to reach a better community awareness is needed.

Our second question, Do you believe saving the snowy plover is important, showed that most people did care. 94% of the people we surveyed said they did care. Even if the people knew nothing about the bird they still felt it was important to save any animal. The general feeling I got from the people we interviewed was yes, I do care about endangered animals but I don’t believe that humans should stop everything they we doing in order to save it. Basically they we saying as long as people don’t shut down all the beaches for this bird then they are happy with helping bring back it’s numbers.


References

Author: U.S Fish and Wildlife Service. Title: Western Snowy Plover (Charadrius alexandrius nivosus) Pacific Coast Population Recovery Plan. Date: May 2001. Portland, Oregon.


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