Overwintering Grasshopper Nymphs (Orthoptera; Acrididae, Tetrigidae)
This subject has come up several times on guide pages, so I thought it might be good to have a little side line that lists species that overwinter as nymphs. To start it off, here is a list of Grasshoppers that overwinter as nymphs, that I know off. Interestingly, but not surprisingly, there is a tendency for many of the species to be close relatives of one another. Most of these lay eggs in spring or summer, and eggs hatch later in summer or fall, and the nymphs live through the winter, usually about half grown, or sometimes almost full grown. Because of this, they are often among the earliest species to be seen as adults each season. A few of these survive in extremely cold climates, and it has been suggested that in the coldest places some of them overwinter as eggs the first year, hatch the second spring or summer, and overwinter the second winter as nymphs. I don't know if this is true, but a few of these range very far north. One, Xanthippus corallipes, ranges from southern Mexico to Alaska - pretty impressive.
There are a number of species that in the south hatch so early in the year, that while it is warm and spring in the south, it is still winter on the calendar. I didn't include these. Also, there are several species that occasionally survive the entire winter in mild winter areas (or in unusually mild winters further north) as adults, but there are also eggs in the ground through winter, and I didn't include these. There are at least a few species that, in the US, mature in autumn, overwinter as adults, and die in spring (i.e. Rhammatocerus viatorius,). There are also species that in southern localities such as south Florida or Texas may be present in any stage of development at any time of year, but further north (if they occur further north) will be found to have a more usual and uniform cycle.
There are a number of species of Katydids, Crickets, Pygmy Grasshoppers, etc. that overwinter as nymphs, but I have not tried to list those here.
TANAOCERIDAE; Desert Longhorn Grasshoppers
Tanaocerus koebelei (nymphs in fall, adults in late winter and spring)
ACRIDIDAE; ROMALEINAE; Lubber Grasshoppers
Dracotettix monstrosus (odd timing of presence of nymphs and adults indicates that there are probably two broods, one hatching and maturing after the winter/spring brood)
Phrynotettix robustus (maybe overwinters in all stages(?), but I've seen nymphs in fall, winter, and spring, and adults late winter through spring and summer)
Tytthotyle maculata (adults are present to early autumn, and perhaps there are two broods per year (?))
ACRIDIDAE; OEDIPODINAE; Bandwing Grasshoppers
Chortophaga australior (apparently can overwinter in any stage)
Arphia granulata (it could be that this one overwinters in several stages of development?)
Lactista aztecus (apparently can overwinter in any stage)
Pardalophora haldemani (this species matures later in spring than most listed here)
Pardalophora phoenicoptera (this species matures later in spring than most listed here)
Pardalophora saussurei (this species matures later in spring than most listed here)
Xanthippus - all species and varieties (aquilonius, brooksi, corallipes, montana, olancha,
etc.). Except for X. montanus, these may all be variations of one species.
Trimerotropis pallidipennis (apparently can overwinter in any stage, in mild climates)
Anconia integra (Based on photos now posted on BugGuide, at least some individuals mature in the autumn; so, it seems
there may be a second brood; or, perhaps some adults survive from spring all the way into autumn.)
ACRIDIDAE; GOMPHOCERINAE + HYALOPTERIGINAE; Slantface Grasshoppers
Bootettix argentatus (seems to overwinter in all stages?)
Amblytropidia mysteca (seems to overwinter as adults also, in mildest regions)
TETRIGIDAE; Pygmy Grasshoppers; Grouse Locusts
Apparently all or at least most species in temperate to subarctic climates overwinter as late instar nymphs and adults. Nymphs and adults can usually be found from autumn till spring on warm days.