Please note, the observations I offer below may be specific to rearing conditions and materials used here on Prince Edward Island in eastern Canada.
Larvae sleeved with good sunlight exposure develop much more rapidly than those in shaded areas. I expect the sunlight and additional warmth, associated with it, speed larval metabolism/feeding activity, and foliage may also be richer in nutrients.
Larvae, especially cecropia and columbia, progress much better when sleeves have minimal amounts of foliage. Again the temperature may be warmer in such an environment with less green foliage to absorb heat.
Trying to get as much foliage in a sleeve as possible to reduce number of times larvae have to be moved is counter productive.
The reduced temperature and poorer air circulation in foliage-crowded sleeves seem to have detrimental effects.
I am more and more often, with good results, putting eggs out (still affixed to paper) rather than hatching larvae indoors and then moving to foliage.
For polyphemus and lunas, I put gravid females in inflated brown paper lunch bags. I date the bags and move females to new bags. A day or so before eggs are expected to hatch, I sleeve a fourteen to twenty foot tall white birch tree with a twelve foot long sleeve. I then poke a hole in the bottom of the lunch bag and pull it over the tip of a birch stem inside the sleeve. The tree is released to its upright position and the sleeve is tied off at the bottom. No tending is needed for 100-200 larvae for the first three to four weeks. As larvae grow, they are divided into smaller groups of approximately thirty-five larvae to a twelve foot sleeve. Usually one additional move (1) 100-200; 2) 35; 3) 35) is required to get larvae to cocoon stage.
I use smaller sleeves (67 inch length with 7.5 foot circumference) for rearing columbia on larch, cecropia on cherry, rosy maples on maple, Smerinthus cerisyi and Catocala relicta on poplar, etc. For the cecropia and columbia, I have been having better success cutting strips of eight eggs, still affixed to lunch-bag-paper, and taping (scotch tape) egg strips to undersides of stems inside sleeves, again doing so a day or two before expected emergence. This can be a tedious procedure but it reduces handling of young larvae.
Usually cecropia have to be moved twice and columbia once or twice. I try to reduce handling and any overcrowding with these two species as they seem more prone to disease.
If the forecast is calling for rain, it is best to move larvae from any nearly empty sleeves a day or so before rain starts. Generally it is not good for larvae to get wet, either in sleeves or in a changing bucket.
I have had fewer problems with birds this summer, but I am still using deer netting over my sleeves (deer netting is tied with string along seams to form a pull-over sleeve).
I usually have no problems with upright sleeves, but horizontal sleeves are still being compromised by birds somewhat when polyphemus larvae are almost ready to spin. I will save small (fifteen footers) upright oaks to finish off polyphemus larvae that can be successfully reared in smaller horizontal sleeves up to early fifth instar.
I had been purchasing Remay cloth, a material designed for use as a garden row cover, to make sleeves. The supplier has changed to a new product which is similar in weight, but new product seems a bit tougher and has a smoother finish so there seems to be less damage with chaffing.
Eacles imperialis pini did well on two different pine species as well as on oak. It took them over a week to pupate, however, inside the small (sandwich sized) ziploc tubs I used for this purpose. Most of the Sphingidae have been pupating in four to five days.
Lunas also did well on beech, provided they got full sun. I will cut out around some of the beech trees I intend to use in the woods next summer to allow for more sunlight.
Due to shortage of available larch trees, I put some columbia larvae out on pin cherry, and many are doing well.
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