2019 martin season is a wrap.

This is one of the last visiting martins of the 2019 season. About eight birds returned last evening with five of them bedding down in this T-10 house. The others stayed in pole H ChirpyNest cavity #25. This scenario has played out for the past week but the number of birds returning has fallen from 20 or so earlier in the week and of course more cavities being used.

It’s been a while since I’ve posted to this space and that is because I enjoyed almost all my free time with my martins. Between nest checks at the two sites I manage, the normal duties of work and keeping up the home place my blog posts have been lax.

I will catch up in the coming weeks with results from my Purple Martin year as well as my trip to Johnson’s Worlds Largest Purple Martin colony and the Purple Martin jamboree.

Mid May season report

Here at my colony site in Abingdon the Purple Martin nesting season is in full speed ahead mode. My first nest check was done on the second of may and while there were over forty nests that had a few green leaves in them none had eggs. I like to count potential nests, those that have green leaves, but until an egg is laid I never know if a pair is going to use it. Once an egg is laid I consider that nest active. At seasons end I use the number of active nests for the season as a monitor of the growth of my colony. The other , more important number I keep close tabs on is the number of nests that fledge young. This is the better gauge of the health and productivity of the colony. Number of fledglings is important but number of successful pairs is just as important for colony health overall.

I am making a strong effort to do a nest check at my home colony every five days during the egg laying time. This is usually into the first week of June. after that I will go to at least every 7 days. mMy second check of the season was May 6 where 13 active and 27 eggs was recorded.

On may 10 I recorded 32 active nests and 109 eggs

today- May 15, 40 active nests and 177 eggs are present in my colony. The only unusual observation thus far was an egg in one of the ChirpyNest cavities, #H-12 , that was broken open. This was one of three present. I can’t recall seeing this before. Ive found eggs pecked and pierced but this was as if it was stepped on and broken in half. The yoke was intact. I removed the egg and will hope the birds add one to replace it.

I also found my first seven egg clutch today in ChirpyNest G-1. This is one on the new ‘Round’ rack. I don’t always get a seven egg clutch so its exciting when it happens.

The martins at the Virginia Highlands Community College site are about a week behind mine this year. The first eggs there were laid on May 9 and at yesterday nest check there are 13 active nests and 41 eggs.

that would put the first eggs to hatch to be around may 25 and at my home colony first eggs to hatch will be about May 18, That is only a few days away. Time is moving on as there are landlords in the south with birds leaving the nest already.

The next two weeks will tell the tale as to how many total pairs my colony attracts this year. I will keep you posted.

The seven egg clutch in G-1 on May 15.

Temperature is warming up and nest building has begun.

It is time for the Purple Martins to build a nest and raise their young. The process has begun and in 50 - 60 days young Purple Martins will be taking wing.

As the season progresses I am monitoring nest cavity temperature of my ChirpyNest housing in comparison to the Troyer horizontal gourd (THG). The THG is a plastic cavity and is arguably the most popular artificial nest gourd available to Martin landlords. Many landlords add additional venting to this gourd in order to make the cavity more hospitable to the nesting martins. The THG I am using has this additional venting in the lid of the access port.

Since April 1, I have been monitoring the internal temperature of three nest cavities in comparison to each other and the outside air temperature. These readings are logged and will be added to a spreadsheet at seasons end. I am using two, dual thermometer units, designed for greenhouse use, that record the maximum and minimum daily temperature. Each cavity has a temperature probe placed just above a pine needle nest bowl of the cavity it monitors. The cavities are labeled

CN-1. A typical ChirpyNest cavity

Air - The air temperature shielded from the direct sun.

CN-2. A ChirpyNest cavity that for the month of April has the Ventilation channel taped in order to study the effectiveness of the ventilation system.

Troyer Horiz. - A lid vented THG.

Last year I conducted this same type study but on a smaller scale. This season will give me a longer term analysis of the effectiveness of the ChirpyNest system. Results of last year’s study can be found here.

Above is an example of a reading from 11:50 on April 17. The readings at that time were as follows.

CN-1. 73.2 degrees

CN-2. 77.5 degrees

Troyer Horiz. 80.0 degrees

Air 72.8 degrees.

From this reading the standard ChirpyNest cavity is 6.8 degrees cooler than the plastic gourd yet only 4/10 of a degree warmer than the air temperature. Even the ChirpyNest cavity with the vent channel blocked is 2.5 degree cooler than the plastic gourd.

I anticipate this cooler ChirpyNest cavity will prevent pre-mature fledging and I have replaced all my plastic gourds with the ChirpyNest for 2019.

While temperature is the measuring factor, overall ventilation is what I see as the key to the improved cavity environment. Think about being in a poorly ventilated room versus one that is ventilated. That is the thinking I have applied. Openings in the bottom of the plastic gourds are blocked as soon as a nest is built and any flow through ventilation comes from the front opening. The ChirpyNest ventilation flows from below the nest tray and does not get blocked with the building of the nest.

The nesting season is under way. Time to enjoy the Purple Martins.

Martins finally have some warm weather.

Martins  March 27, 2019 Wednesday

Today the temperatures are going toward 60 degrees for the first time in a while.  After my first arrival on the 15th and his departure a couple days later, hopefully going back to a more suitable area, My Martin returned on Sunday the 24th.  Joining him were another male and a female on Monday and today I count three male and one female at my Peaceful Valley Purple Martin Site. 

Other colonies I monitor have a few martins back now too.  Yesterday I counted three at the VHCC site, and another landlord called to report as many as five martins at her site on Monday March 25.  It is becoming a pattern I noticed over the years that The first few Martins of the year will usually arrive and be greeted by poor weather and be forced to retreat. They  then return a week or so later when the weather improves.   Of course there is the chance that the first bird (s) perishes  in the poor weather before being replaced by later arrivals.

I look forward to more arrivals in the next few weeks as we finish this first week of spring. Reports of martins down south,   nest building are coming in on the Purple Martin Facebook pages as well was the first reports of martins arriving in  the more northern states.