Ask SIB – Size of Opening for a Carolina Wren Nest Box

QUESTION: Every year Carolina Wrens nest in my front and backyard, either in the hanging plants, generic birdhouses I’ve received as gifts, etc. This year I bought some wren houses from Woodlink but the opening is only 1″ round. In googling it, I see “expert” sites contradicting themselves – recommending 1 1/8 or 1 1/2 or larger, depending on whether attracting House Wren, Carolina Wren, etc.) Anyone know what size I should enlarge it to?


ANSWER: Good question, which is my statement any time I do not know an unequivocal answer.

I do know that Carolina Wrens are opportunists nesting in cavities or any tight area like a planter as Mary has experienced, crotch of a tree, old pair of pants hanging in a garage (personal experience), or vine tangles. They can nest in a box with a 1 inch hole or a box up to a 1.5 inch hole, the recommended size for the Eastern Bluebird or larger. Most places recommend a 1 1/8 inch hole for Carolina Wren and 1 inch for House Wren. One of the primary reason for having a small hole is to prevent House Sparrows and European Starlings from using the nest. Neither of these species are an issue on Seabrook Island.

Choosing a larger hole opens up the potential for a variety of species to use your box.

Regardless of the size hole chosen, one may find that the House Wren will eventually usurp the box, most often filling it to the brim with sticks so the box cannot be used by other birds. Unlike the Carolina Wren, the House Wrens have a strong preference for nest boxes and more open, less shrubby areas.

One of the way to manage and encourage Carolina Wrens is to be ready early in the season. They should be laying eggs by mid-March. The House Wren will not be laying eggs until the first of May. This behavior allows the Carolina Wren to have its first brood prior to the House Wren even starting. The Eastern Bluebird starts in Mid-February.

Hope this helps.

Bob Mercer, SIB’s “Resident Naturalist”

Ask SIB: What Species are “Henry & Henrietta?”

Lake House resident Red-shouldered Hawks, Henry & Henrietta

Question: Does anyone know definitively what type of hawks are pretty much living behind the Lake House? I’m thinking red shouldered, since tail has black and white bands when flying. I call them Henry and Henrietta.

They can often be seen sitting on the bird house next to the lake, or on the roof, or the slats outside the exercise room. Today one of them perched there and then bent down and peeked inside at Melissa teaching.

Diane Allen, SIB member

The answer is a Red-Shouldered Hawk. You can learn more about this beautiful bird of prey by visiting the Cornell Lab of Ornithology “All About Birds” website. On Seabrook Island, they are often seen year-round near the Lake House, at the Equestrian Center and near the Recycling and Garden area.

Ask SIB if you have a bird related question.

Ask SIB: Where Have All the Pelicans Gone?

Sofia, 13-month old granddaughter of Dick & Marg Wildermann

SIB Received this email on Sunday 8/16/20:

Dear SIB

Our daughter has been renting a villa on Rolling Dunes, next to boardwalk #1, for two weeks.  We spend part of most days there, especially in the evening.  For two weeks, our 13-month old granddaughter, Sofia, loved being out on the porch or deck in the evening to watch the pelicans fly directly overhead.

The pelicans came over constantly, in groups of several or even 20 or more. We’ve noticed when walking the beach as well that there are many pelicans this year.

Well, Saturday evening there were very few pelicans flying over their villa in the evening.  On Sunday there were none.

Where have the pelicans gone? 

Sofia will be here for another week.  I promised her that SIB would bring the pelicans back.  So you now bear a heavy burden.  

Thank you,

Dick Wildermann

And then we received this follow-up note on Monday 8/17/20:

SIB friends:

We took Sofia to the property owner’s pool at North Beach today and there were lots of pelicans.  Thank you so much for taking care of our problem so quickly.  Sofia would point at them flying overhead and screech.  She loves pelicans.

I told her the SIB experts said we saw no pelicans yesterday because it was Sunday and they had taken the weekend off.  I hope that was the right answer.

Keep safe, Thank you, with love, Sofia

Dick Wildermann

Her mom, Jodi added,

Thanks! She’s a real birder already. She loves nothing more than the birds, especially the pelicans. She hasn’t learned yet that screaming at them chases them away rather than attracting them though.

Jodi Simopoulos

Besides having the weekend off, the only other explanation we at Seabrook Island Birders came up with is that the weather had changed and the Brown Pelicans had different flight patterns as directed by the Pelican Air Control (PAC). But in all seriousness, as this is a question many of our island residents and guests have asked, there probably is no logical reason we mortal humans could discern. Weather, tide, winds, fish schools, … all would have a bearing the pelicans would understand.

Ask SIB: Why is this Northern Cardinal Doing This?

This is a common question we receive from Seabrook Island Birder (SIB) members! Have you ever seen this behavior at your home?

We have a female cardinal that continues to try and get into the house. Generally 3-4 times a day she flies up the window sometimes she perched on the sill looking in. This has been going on for over four months.

Christine Dennis

For starters, rest assured the bird is not trying to get into the house. During the breeding season, birds aggressively attempt to drive off intruders of the same species. This is an instinctive behavior and not something the bird can control. What you are experiencing is a bird that sees its reflection in your window and instinctively attempting to drive the intruder away. The process follows a pattern. First the bird sees its reflection. Thinking it is an intruder, it displays a warning posture. Needless to say, the reflection responds with the same threat. This quickly accelerates to a full out attack. This is not something the bird can understand or learn not to do. 

The solution is to change the reflectivity of the surface the bird is attacking. This is easier said than done! There are several things you can try, none of them visually appealing. Some people have had success with strips if different color paper taped on the inside of the window  to break up the image. Completely covering the reflective surface on the outside works, but it also blocks the window. Installing screens will break up the reflection and soften the blow if the bird does hit the window. Finally, some people tie moving objects, pie tins, ribbons, etc., around the area to create movement that scares the bird away.

All that said, the bird will not hurt itself, will not break or damage the window, and will stop eventually when the breeding season ends.

Bob Mercer, SIB’s “Resident Naturalist”

Thanks to dlinnehan, we found this video on YouTube which provides great footage of both male and female North Cardinals attacking their own reflection.

Seabrook Island Birders (SIB) welcome questions from our community of birding friends! If you have one, just fill out the form on our website or send us an email!

Ask SIB: How to Keep Ants off the Hummingbird Feeder

Is there any way to keep ants out of my Hummingbird feeders? There is a little cup in the middle that is supposed to keep them out but nonetheless they crawl in through the ports, then get trapped and most of them drown.

Melodie Murphy

To keep ants off of a hummingbird feeder, you need to create a water baffle. If your feeder is a hanging feeder, they sell them wherever you get your feeder supplies. Essentially,  you are placing a small reservoir of water between the hook and the feeder. The ants cannot get passed the water. This needs to be kept full.

Bob Mercer

Seabrook Island Birders (SIB) welcome questions from our community of birding friends! If you have one, just fill out the form on our website or send us an email!

Ask SIB: How Do I Keep Squirrels Out of My Feeders?

Seabrook Island Birders (SIB) welcome questions from our community of birding friends! If you have one, just fill out the form on our website or send us an email!

I’m having a problem with pesky bossy squirrels that are cleaning out my bird feeders taking the great majority of the seed. I read that one can add cayenne pepper and crushed red pepper into the seed before putting it into the feeders and that this will deter the squirrels but not the birds (as they do not have taste receptors for capsaicin). As the bird expert, do you know whether or not that adding the pepper to the feeders will not hurt the birds and if not, approximately how much one needs to add?

Leslie Baylis

Quick response : Hi there!  You are correct – In fact you can buy suet with red pepper at Wild Birds and I can attest it works that squirrels don’t like and birds don’t mind. But let’s ask our “resident naturalist,” Bob Mercer, to see if he has any more details.

Nancy Brown

Nancy, you are right. Mammals do not like red pepper and birds don’t react to it. Some people think it is cruel for the squirrel, especially if they rub their eyes. I think a little shock therapy goes a long way. As to the amount, that is another question. The common wisdom is birds can tolerate 20,000 parts per million (PPM) while mammals can tolerate more like 20 PPM. So, you do not need a lot. One source, which is totally anecdotal suggested a ¾ cup for a 40 lb. bag of seed. Squirrels are quick learners, so if you do not get it strong enough the first time, who knows how they will behave. One word of caution! Red Pepper is a problem for us also. It can be a skin irritant and if you get it in your eyes, it will most likely involve a trip to the hospital, especially if you are working with large quantities. Do not shake the pepper flakes into your bird feeder on a windy day! Mix it inside.

My suggestion if you want to go this route is to try a ½ tsp of either Cayenne pepper or Red Pepper flakes in each feeder and see if it works. If it does, you should be able to reduce to ¼ tsp or even eliminate adding the pepper flakes once the squirrels are trained to stay away, repeating the process only when they catch on that you are no longer using the flakes.

Bob Mercer, SIB’s “Resident Naturalist”

Thanks, both Nancy and Bob. I put some cayenne pepper in the feeder on Wednesday afternoon and saw the squirrels yesterday (Thursday) but not up on the feeders- they were nosing around on the ground. However, today they’re not even under the feeders so I think this approach worked. Thank you both for your help. Now, maybe you have some wise advice about the deer eating the plants…

Leslie Baylis

Ask SIB: Nesting Anhingas

Seabrook Island Birders (SIB) welcome questions from our community of birding friends! If you have one, just fill out the form on our website or send us an email!

Breeding Anhinga pair vs Great Egrets – photo by Valerie Doane

I’ve seen a male and female Anhinga, I assume a mating pair, on Jenkins Point Road in the lagoon rookery on the right.  You know better than I that there are only a few Egret nests in that rookery.  I noticed on several different visits over the last 10 days or so that the Anhinga pair was sometimes sitting on a nest and sometimes they were not and sometimes they were in a big time squabble with a pair of Great Egrets over the nest!  I have photos of the squabble on June 1st.  I swear the Egrets and Anhinga pair were fighting over the nest!

I was wondering about a few things and thought perhaps you might have some insight on the following:

1.     Do these two species often steal each other’s nest? 

2.     Do Anhinga’s typically nest in the same rookery as Egrets?

3.     Isn’t it late in the season for chicks to hatch? 

Valerie Doane

So for some quick answers, Nancy Brown responded as follows (be sure to “Read More” to see the answers and more photos!):

Continue reading “Ask SIB: Nesting Anhingas”

Ask SIB … What can I do for Starling invasion?

We often receive questions about birds from our members and residents of Seabrook Island. This week, Carl recently sent us this question:

Starlings have taken over my feeders. They discovered it about a month ago. Now they arrive each morning and occupy every feeding slot for hours, consuming lots of birdseed and depriving the finches, chickadees, titmice, cardinals, wrens, sparrows, etc. With the starlings dominating the feeder, I doubt that we will see painted buntings this year.
Will these starlings move on or is this the new normal?
Any suggestions?

Carl, Deer Point
European Starlings at Feeder – Birdwatching HQ

Joleen Ardaiolo provided the following response:

This is a great question and one that most people who have bird feeders have needed an answer to at one time or the other, especially with various species of “bully birds.” I have had problems in the past with American Crows, Boat-tailed Grackles, and even Blue Jays at the end of their nesting season. Your question comes at an interesting time because at present, I am  having the same issue with Red-winged Blackbirds.

Because I have had problems in the past with bully birds, I had already made some adjustments to the feeders I use.  First, I decided to use smaller tube feeders. These have smaller perches that make it more difficult, even though not impossible, for large birds to perch on comfortably to eat. If the large bird does land on this feeder it won’t stay long. You might think that you will need to fill these feeders more often, but if you just have smaller birds eating at these feeders, you probably won’t be filling them more than once a week. Also, leaving seed in a tube feeder much longer will result in the seed at the bottom going rancid.

I also have used cages on my tube feeders when certain bully birds were being aggressive. These allow only small birds to get close to the feeder. This might be a great option for Painted Buntings since I have read that they are not group feeders. You could put out a couple small caged tube feeders that only contain millet, their seed of choice. Perhaps feeding inside the cage will make them feel more protected.

As for the other birds that you want to attract, I have found that using a tray feeder with a dome top works really well. The dome top is adjustable to only allow in the size bird that you want to feed. I have mine adjusted to allow in birds up to Northern Cardinal size and fill it with sunflower and safflower seed to make everyone happy.

One of the staff members from Wild Birds Unlimited also suggested I bring in my feeders for a few days to encourage the offending birds to go elsewhere for their snack. I read that European Starlings are ground feeders, so eating from your feeders might be more opportunistic than natural for them. I have seen flocks of Starlings on the ground at the Equestrian Center and farm fields so they might just need to be urged to move on.

I am hopeful that these suggestions will help, but I would also like to encourage anyone else who might have had success with getting rid of bully birds at their feeders to respond to this post.

If you have a question for SIB, either use this link or send an email to

Ask SIB … What is that Bird?

We often receive questions about birds from our members and residents of Seabrook Island. This week, Jenni sent us an email along with some photos.

I’ve been watching the birds at my feeders for few years now and saw something new today! I’ve attached some photos of this beautiful white mystery bird. Thanks for your help! 

Jenni, Oyster Catcher Court

After reviewing the photos, we suspected it might be a leucistic Brown-headed Cowbird, since it is hanging with the Brown-headed Cowbirds, and it’s shape certainly looks like one. We asked for input from SIB member Bob Mercer, Retired Director/Naturalist, Silver Lake Nature Center, Bristol, PA. He responded, “If it were not for the few smudged of brown, I would say albino Cowbird as it has the red eye. Because of the brown, I agree with your assessment.”

After letting Jenni know, she responded, “Thank you! The crowd passed through again this morning, and the white bird was hanging with the Cowbirds. I did notice they have the same mannerisms when eating, same size, same tail feathers. So much fun! “

Leucism is a condition in which there is partial loss of pigmentation in an animal—which causes white, pale, or patchy coloration of the skin, hair, feathers, scales or cuticle, but not the eyes. This is the same thing that causes the coloration of the Piebald White-tailed Deer on Seabrook Island.

To learn more about this and other types of “unusual” birds, visit the Project Feederwatch website.

If you have a question for SIB, either use this link or send an email to

Birds of a Feather Plus Friends Flock Together

Question:  The American Robins recently have arrived in flocks to my yard.  At the same time, Cedar Waxwings also came in mass.  All summer, I saw only occasional Blue Jays but their color is now interspersed with the Robins and Waxwings.  Why are these birds normally seen individually or not at all and suddenly they are here at the same time?  Submitted by Judy Morr

American Robin – Ed Konrad

It is not uncommon to see different species of birds flocking together in the fall and winter. At this time winter birds work together to find food that is sparse compared to the abundance available during the warmer months. The more eyes, the better for locating food sources. Recently, during one of the Early Morning Bird Walks at Caw Caw we noticed Cedar Waxwings and American Robins together in trees feeding on berries.

Cedar Waxwing – Ed Konrad

These two species are apparently common traveling partners in the fall and winter. Dozens of birds would fly up in mass to the next tree that looked promising for a better feed. There is no competing when there is a bounty of berries. It is interesting that Cedar Waxwings are social birds year round whereas American Robins know the benefits of grouping together during the cooler months, but become territorial in the spring during nesting season. For more information check out Robins and Waxwings in Winter and Summer Comparing Behaviors.  Agricultural fields, which are abundant around John’s Island, are another area that you might see mixed flocks feeding on grain and seeds remaining after the harvest. 

A single bird in a flock is also safer because there are many other birds to look out for predators, such as hawks or owls, as he eats or rests. A hawk cannot easily pick off a single bird crowded with others as they perch on power lines or in trees. I’m sure most people have noticed a hawk being chased away by a swarm of smaller birds. Interestingly you may also see a couple of Blue Jays together with Robins on a lawn during winter months. Blue Jays may raid a Robin’s nest for eggs or hatchlings during nesting season, but are more interested in acorns, seeds, and insects in fall and winter and are excellent alarms for incoming predators. 

Frigid nights will also bring birds together. A tight knit flock roosting in trees at night offers a greater defense from the cold winter weather. BirdNote, a wonderful short daily podcast, recently released 61 Tons of Robins! about how many American Robins were counted in Florida roosting together at night. 

So, it appears that birds engage in activities that are beneficial to their survival. Large numbers of birds and even different species will flock together in fall and winter when they are more vulnerable to the elements in order to locate food, keep warm, and stave off predators.  

Submitted by: Joleen Ardaiolo

Photos by: Ed Konrad