TREE SWALLOW ~ PURPLE MARTIN If you live where there are lots of tree swallows and/or blue birds, and you've been UNSUCCESSFUL AT ATTRACTING PURPLE MARTINS... READ ON:
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BLUE BIRD ~ PURPLE MARTIN
I N T E R F E R E N C E
THIS MAY BEAN EMERGENCY!
DAN'S RULES FOR MANAGING INTERFERENCE
RULE ONE: NEVER ALLOW A TREE SWALLOW OR BLUE BIRD TO NEST IN YOUR MARTIN HOUSING RULE TWO: NEVER DENY AN INVESTIGATING MARTIN ACCESS TO YOUR PM HOUSING RULE THREE: RULE ONE IS MORE IMPORTANT THAN RULE TWO
These rules have been visualized as a teeter-totter over the past season by landlords using the "protocol" below. The teeter totter is visualized as below:
[Try to memorize it, as it might govern your actions for a significant period of time!]
NEVER ALLOW A TREE SWALLOW OR BLUE BIRD TO NEST IN YOUR PM HOUSING __________________________
INEVER DENY AN INVESTIGATING MARTN ACCESS TO YOUR PM HOUSING
THE PLAYERS IN THE INTERFERENCE GAME
Usually a tree swallow pair will prefer a gourd; but they have also been reported to compete with martins for "apartment style" housing. Blue birds prefer a "box" or similar type housing... but may also choose a gourd. If you allow tree swallows or blue birds to nest in your PM gourds (or housing) they will completely dominate your entire gourd rack... or PM site and all the air space around it for at least 25 feet... and you can expect NO MARTINS this year Regardless of how little time might remain in the "martin season" for attracting martins to your new site, the following protocol MUST be followed to eliminate the TS/PM interference and give you a chance to get martins... and a cohabitation of both martins and tree swallows at your site.
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| The Eastern Blue bird | The Tree Swallow | Adult female purple martin |
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The best agent(s) to protect your uninhabited prospective martin housing from tree swallows is "a committed pair" of tree swallows located 25 to 35 feet away! The same is true for blue birds. |
INITIAL ACTION will depend on WHEN you discover that you have "interference" at your site from tree swallows or blue birds [or both.]
- PRO-ACTIVE management occurs when a landlord identifies his problem before the arrival of the martins at the beginning of the season. PROactive management of TS or BB interference will require the landlord to configure his PM site as in step two below.
- PRO-ACTIVE management is planned for during the winter and initiated PRIOR to the return of the tree swallows and/or the breeding season of the blue birds! Configuring PROactively for TS and/or BB interference gains the landlord of an unestablished site AT LEAST A MONTH'S advantage over a landlord who discovers interference AFTER the return of the martins to his/her latitude.
- RE-ACTIVE management is required (usually in the "surprise" mode) because the discovery (or enlightment) that TS or PM interference is occuring (or has occurred) at your site.
RE-ACTIVE management occurs at whatever time an interference problem is first noticed. Although, this sort of management is NOT DIFFICULT, it is often "stressful" because it is NOT planned for and often requires action unfamiliar to a rookie landlord and resources not on hand.
STEP ONE: STEP BACK, SHUT DOWN, AND MAKE A PLAN!
- COMMIT YOURSELF TO THE VISION OF A "PROTECTIVE CONFIGURATION."
- This means you will be "forcing" a pair (of each) of the interfering species (BB and/or TS) into housing 25 to 35 feet from your PM housing. With this geometry, the TS and/or BB (both fiercely territorial within their own species) will protect your PM cavities from invasion by any other members of their own species.
- At these distances, the TS and/or BB will allow determined martins to visit and inspect your PM housing... even though there will be initial "squabbling" and SOME martins will not be determined enough to tolerate the squabbling (especially SY's who are shy by nature, and ASY's who are just exploring and not truly in "house hunting" mode.)
- At closer distances (especially if actually nesting in a PM cavity or within 15 feet) both TS and BB behavior seems to be governed by BOTH territoriality AND offspring protection instincts... the combination of which causes their harrassment of PM visitors to be intolerable to all but the most determined and experienced of martins.
- At farther distances, (35 to 100 feet) you will get only temporary protection for your PM rig because TS and BB territoriality is MAXIMAL early in the season. However, the territory of both TS and BB shrinks progressively as the season goes on... and MIGHT shrink to 40 feet or even less when both parents are busy feeding chicks
- THE GEOMETRY IS CRITICAL! The assertions just above explain why. Read them again if you have doubts about why the 25 to 35 foot rule is a "MUST" to follow.
STEP TWO: SET UP ALTERNATIVE "DESIGNATED" HOUSING!
- IMMEDIATELY shut down your PM housing.
- This means lowering... or at least closing all PM compartment openings.
- In the case of gourds, it's even ideal to remove them and "hide" them in the garage or the basement... at least till you are sure there are martins in your area.
After closing your PM cavities, SET UP "ALTERNATIVE HOUSING" for your tree swallow and/or blue bird pair!
This "designated housing" must be located about 25 to 35 feet from your main PM housing.IF YOUR "PROBLEM" TS OR BB PAIR HAS ALREADY BUILT A NEST IN ONE OF YOUR GOURDS, carefully remove that gourd [without disturbing the nest] and locate it on a Shepherds hook or other device 25 to 35 feet from your main PM housing.
- IF YOUR "PROBLEM" TS OR BB PAIR IS NOT NESTING, Then use a gourd or blue bird house as the "alternative housing" and place that 25 to 35 feet from your main PM rig.
- IF YOU ARE DEALING WITH BOTH TS AND BB... OR THINK YOU MAY GET BOTH, you should configure for both.
STEP THREE: "FORCE" YOUR TS or BB PAIR INTO THEIR NEW HOUSING!MODIFY THE ENTRANCE HOLE (if needed) as time permits. If "sacrificing" a PM gourd... or using housing with an entrance larger than 1 1/2 inches, it is good to modify the entrance to 1 1/2 inches. This size opening is perfect for both tree swallows and blue birds. It will also make them starling proof. Remember both BB and TS are much smaller birds than purple martins! WHAT IF AN "EVICTION" or "INVASION" OCCURS... or some OTHER species claims one of your designated BB or TS houses? Evictions and/or "surprise invasions" are common... especially by chickadees. This is the simplest problem of all to deal with. You simply add additional housing to your configuration to replace the "stolen" or "invaded" TS or BB house. Try to maintain good distance (at least 15 feet) between the housing when you re-configure... and keep all the entrances faced so "everybody can see everybody."
- THE FIRST ACTION: The closing of your PM cavities and providing the "designated housing" in the correct geometry is only the beginning of the process we are calling "FORCING."
- THE SECOND ACTION: YOU MUST MAKE TS and/or BB HOUSING SCARCE . over whatever territory you control. This action is the most important chore of step three. At this point, if you had a magic wand and a fast horse, you would ride throughout the entire kingdom and CLOSE ALL TS/BB HOUSING till you get YOUR TS or BB committed to their "designated housing." This is the most-often-forgotten part of the protocol and failure to do this can cause serious delay or failure! Remember that if there is LOTS of potential housing nearby for tree swallows and/or blue birds (gourds, boxes, and other cavities) there is NOTHING to keep your "designated housing" from being their LAST choice, when you want it to be their FIRST (ONLY) CHOICE.
- A SPECIAL "TRICK" FOR TREE SWALLOWS: ..
THE McKINNON FLASHER
(shown at right.)These are easy to make, and require only a piece of string and an all-white sour cream or cottage cheese lid or the like. Using your best cub scout or brownie skills, trim the white piece from round to oblong to mimick the shape and size of the tree swallow breast and under belly. Then hang it (well) above or below the entrance of your new "designated alternative TS dwelling" ...being sure to keep the string well away from the opening to avoid entanglement.
These little charmers DO work! It is assumed that they serve as a visual "stimulus" by mimicking the "in flight silouette" of a tree swallow as they blow in the breeze.
ANOTHER REMINDER ABOUT "EVICTIONS" and "INVASIONS" These will usualy occur during step 3. If some OTHER species claims one of your designated BB or TS houses? Evictions and/or "surprise invasions" are common... especially by chickadees. This is the simplest problem of all to deal with. You simply add additional housing to your configuration to replace the "stolen" or "invaded" TS or BB house. Try to maintain good distance (at least 15 feet) between the housing when you re-configure... and keep all the entrances faced so "everybody can see everybody."
STEP FOUR: RIDING THE TEETER-TOTTER A PERIOD OF WATCHFUL WAITING.
IMPORTANT SPECIAL NOTICE: Earlier versions of this protocol "limped" because of inadequate research and experience to provide a set of "rules" for allowing landlords to allow ANY martins access to inspect the PM housing. The present version presents a set of rules & guidelines which are thought to be valid based on three seasons of experience and research. "Riding the Teeter-totter" is a metaphor created for implementing ("juggling") the rules to allow you to use attractants and actually allow martins access to your PM rig during the protocol.
WANT TO "GO AFTER" THOSE RETURNING ASY MARTINS AT YOUR NEW SITE?
READ ON... YOU MAY DO THAT... BUT FOLLOW THESE RULES!THE CARDINAL RULE IN THE PROTOCOL REMAINS THE SAME:
THE "PROBLEM" TREE SWALLOW OR BLUE BIRD PAIR MUST BE COMMITTED TO THE NEW HOUSING before you should raise and open your PM housing again without monitoring.
The word "committed" ideally would mean their depositing of an egg in the new accommodations. But, often there is not time to wait... and therefore most experts feel it will be "safe" to open the PM rig earlier... such as when nestbuilding is well along! Later in this section there is a "scoresheet" for measuring TS committment. CLICK HERE or scroll down to see the "scoresheet." But, regardless of when you decide to re-open the PM cavities, BE AWARE OF THE COROLLARY RULE:THE COROLLARY RULE IS ALSO CRITICAL:
UNTIL YOUR "PROBLEM" TS OR BB PAIR COMMITS TO THEIR DESIGNATED HOUSING, NEVER TURN YOUR BACK ON THEM WITH YOUR PM CAVITIES OPEN.
To do this would be to invite the disaster of a TS or BB invasion... and would probably ruin your chances of getting martins this year.DAN'S RULES & THE TEETER TOTTER APPLY SPECIFICALLY TO THIS SECTION (STEP 4.)
They are repeated here from above:
D A N ' S R U L E S RULE ONE: NEVER ALLOW A TREE SWALLOW OR BLUE BIRD TO NEST IN YOUR MARTIN HOUSING! RULE TWO: NEVER DENY AN INVESTIGATING MARTIN ACCESS TO YOUR PM HOUSING! RULE THREE: RULE ONE IS MORE IMPORTANT THAN RULE TWO AND TAKES PRECEDENCE!
T H E T E E T E R T O T T E R
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NEVER ALLOW A TREE SWALLOW OR BLUE BIRD TO NEST IN YOUR PM HOUSING __________________________
INEVER DENY AN INVESTIGATING MARTN ACCESS TO YOUR PM HOUSING In the game of "riding the teeter-totter" it important to remember that rule one (on the left) takes precedence and TOTALLY GOVERNS when you are not there.... in case you can only monitor the site part of the time.
MONITORED VERSUS UN-MONITORED PROCEDURES:
- If you are NOT able to monitor your site closely, then you MUST allow rule one to govern your procedures. This means you will need to keep your PM housing closed (and Dawnsong off) until your TS and/or BB are committed.
- If you CAN monitor your site closely, then you may engage in the "newly coined" process of "riding the teeter-totter. This metaphor involves "juggling" the two principles on the ends of the teeter totter... stretching "rule one" to allow you to call in martins to investigate your site (even at the beginning of the season, in attempt to get "the priviledge" of an ASY martin visit.)
A "QUICK RELEASE" CAVITY OPENING SYSTEM
FOR "RIDING THE TEETER-TOTTER WITH BB and/or TS
THE SUMMARY RULE FOR STEP 4:
- WHEN YOU CAN MONITOR YOUR SITE CLOSELY,you may "ride the teeter-totter and "juggle" the two key rules. [A "quick release" cavity-opening system is useful for this phase of things.]
- WHEN YOU CAN NOT MONITOR YOUR SITE CLOSELY, then it is necessary to let "rule one" prevail as in prior versions of the protocol... and you will have to "wait it out" until your TS or BB are committed!
HOW TO JUDGE WHEN TREE SWALLOWS ARE "COMMITTED"
[Blue bird committment is probably very similar except for the "divebombing" habit.]
CONSIDER THAT 100 POINTS = COMMITTMENTTS PAIR PERCHING TOGETHER: 10 POINTS!
This can happen anywhere from 2 days to 4 weeks following return of the TS in the spring.TS PAIR DEFENDING TERRITORY: 20 POINTS!
This will usually be seen as soon as you notice a "perching pair."
It is not likely that they would be "paired up" and NOT defending territory.FEMALE CREATES "NEST BOWL" AT BACK OF GOURD OR IN HOUSE: 20 POINTS!
Generally you will see the little nest bowl fairly soon after the "couple" pairs up
...figure 1 to 5 weeks after their arrival in the spring.COPULATION OBSERVED: 20 POINTS!
TS FEMALE BEGINS "FEATHERING HER NEST:" 20 POINTS!
Figure 2 to 6 weeks from time of arrival.TS DIVEBOMB LANDLORD WHEN APPROACHING OR CHECKING NEST: 30 POINTS!
This is the real "hooker" in the program.
Some participants had the feeling that divebombing was a SURE sign of committment.
If you've ever been divebombed by a TS, then you'll know why it can suggest LOTS MORE than 30 points.
There can be NO DOUBT that TS engaged in divebombing are committed to something!!!!!!
Be aware that divebombing MIGHT occur earlier than it is listed here...
sometimes even before you notice copulation or feathers.FEMALE TS LAYS FIRST EGG IN NEST: 100 POINTS!
Please recall that this "scoresheet" is only a working draft at the present time... as well as a REQUEST FOR AMMENDMENTS AND ADDITIONS. It is NOT the holy gospel according to ANYBODY... and I am eager to have feedback on this!
Regardless of how (or when) you make the decision to re-open your PM housing and resuming Dawnsong, WATCH CLOSELY for any sign that the TS or BB pair might resume their attempt to nest in your PM housing. DO NOT BE CONFUSED BY THEIR PERCHING! They will continue to perch often on your PM pole and other rigging... especially if it is the highest thing around. Most likely they developed the habit of perching there BEFORE you identified the "interference" problem in the first place... and you need NOT worry about this perching habit. Just BE SURE THEY ARE NOT NESTING AGAIN IN YOUR PM HOUSING. If they do, then you must quickly "revert" back to step three. Once they are nest building in their "separate accommodations" they will usually continue to perch on your PM pole but will not show any interest in the gourds or housing... as by "inspecting" or entering the cavities anymore.
There is no substitute for patience. One must wait for Mother Nature during this protocol. Haste will bring disaster!... which means that raising your PM rack too soon [BEFORE the TS or BB are committed to the new "alternative housing"] leaves your site vulnerable to the disaster of invasion by TS or BB with domination of your entire martin rig... and probably NO MARTINS this year! It is reassuring, however, to remember that the waiting tends to be shorter as the season gets later. By the time the SY martins are arriving, ALL BB and MOST tree swallows are quite ready to nest and will usually not keep you waiting long during step three. (above) ANXIETY REDUCTION
In time, this emergency page will be replaced by a more complete article which will outline the characteristics and habits of tree swallows and martins and will better explain the IMMENSE BENEFITS of having both TS and PM at your site. It will also better explain why the above protocol works. For now, it must be enough to realize that once your TS or BB pair is nesting just 25 to 35 feet away from your PM rack, they will do an absolutely thorough job of "running off" all other members of their own species and many other species who would want to nest in your PM housing. [House Sparrows and Starlings, must still be eliminated by humans, of course.] With the tree swallows near-by, your martins will be subjected to some mild to moderate harassment at first... but this is something that nature prepares them for. The noisy "squabble"that will happen when martins arrive at your site is a "battle" that martins can AND DO WIN! The TS and BB may not "like it" ...but they do know the pecking order... which typically involves the martin pecking the TS or BB right in the face. [This is not an exaggeration or metaphor... It is actually what you will see when a martin decides to "move in" on new site with TS or BB on hand.] Within a very short time, the tree swallows and martins will get along fine... and often will even share perches. HOW AND WHY DOES IT WORK
A FREQUENTLY ASKED QUESTIONS section... and other additions and revisions to this protocol are underway. Please keep a bookmark on this page (add it to your "favorites") if you are involved with TS or BB interference at an Unestablished purple martin site.
Please send corrections or recomendations to: Dan Drew
Please post "remarks" or "experiences" on the Purple Martin Forum.
Copyright, 2002: Daniel C. Drew, M.D.