Phenology of weight, moisture and energy reserves of Australian monarch butterflies, Danaus plexippus

Abstract

1. In the Sydney area of New South Wales, dry weights of reproductive monarch butterflies averaged 156 mg and were higher during winter than in other seasons. Dry weights of non-reproductive monarchs ranged from 216 t o 324 mg and declined by 1~2 5 % during overwintering.2. Fat in reproductive butterflies ranged from 0.009 to 0.017g/O.lg dry weight and was lower during winter than in other seasons. Fat content of nonreproductive monarchs washigher (0.019-0.037 g/O.1 g) and declined by 24-51% during overwintering.3. Lean dry weights of reproductive monarchs were lower than those of nonreproductive individuals. Lean dry weights of non-reproductive butterflies increased rapidly at the beginning of overwintering and remained high throughout the winter. Analysis of protein content indicated the higher lean weight of non-reproductive monarchs was due to greater protein levels.4. Moisture content of monarchs did not vary with season or reproductive status and appeared t o be correlated with ambient humidity. 5. Non-reproductive monarch butterflies in New South Wales adjust biochemically during overwintering. Energy reserve dynamics of these butterflies are comparable to those that occur in non-reproductive monarchs in North America.

The effect of adult feeding on lipid and protein reserves in African armyworm, Spodoptera exempta, moths before and during reproduction

“…The high levels of abdominal lipid in newly emerged S. exempta, supported by ultrastructural evidence (A. Gunn, unpublished results), show that like other Lepidoptera such as Prodenia eridiana (Stevenson, 1968(Stevenson, ,1969 grandiosella (Chippendale, 1971), Danaus plexipus (Cenedella, 1971;Brown & Chippendale, 1974;James, 1984), S.exempta accumulates large quantities of lipid reserves during the larval stage which are held, probably as triglycerides, in the fat body (at emergence the oocytes are immature and constitute a small proportion of the abdominal lipid as well as protein and carbohydrate). As in P.eridiana (Stevenson, 1968), glycogen is present in only small quantities.…”

Monarch butterfly preference and use of nine Midwestern milkweed species

“…The lipid content of freshly eclosed monarchs was similar to previous studies in which monarchs were collected in the field and reared in the laboratory (Beall 1948, Cohen 1985, James 1984, Brower et al 2006, Brower et al 2015.…”

Investigating the poor performance of heather beetle, Lochmaea suturalis (Thompson) (Coleoptera: Chrysomelidae), as a weed biocontrol agent in New Zealand: Has genetic bottlenecking resulted in small body size and poor winter survival?

“…Furthermore, Renault et al (2003) found survival at cold but non-lethal temperatures was positively correlated with insect body size in Alphitobius diaperinus (Coleoptera: Tenebrionidae), and larger insects lost weight at a slower rate than smaller ones. Overwintering can require a high proportion of pre-winter lipid reserves with death occurring in insects in which lipid levels drop to low levels (Alonso-Mejía et al, 1997;James, 1984). In NZ, larger heather beetles collected from the field at the start of winter have a higher proportion of their body weight as lipids than smaller beetles.…”