Host plants:
The caterpillar lives on thistle species (Asteraceae). The main host plant is Cirsium eriophorum. In addition, some populations live on other thistle species such as Cirsium arvense or Cirsium tuberosum.
Habitat:
Zygaena brizae inhabits mainly sunny, rather mesophilic mountain slopes, which are extensively grazed. In the French Alpes-Maritimes, I found Zygaena brizae on mesophilic to moderately dry pastures in 1400 to 1600m above sea level, where Cirsium eriophorum grew. There are also populations known in dry hillsides and edges.
Life cycle:
I found the hibernated and already active again caterpillars in the Maritime Alps (Vésubie Valley) in late April 2012 at altitudes between 1400 and 1600m above sea level. The caterpillars are quite conspicuous at this time by their feeding pattern - whitish mines. The caterpillars are mature between May and June, depending on the altitude.
The moths fly rather early from late May to late July. The main flight period is expected to be in the Southwestern Alps in the second half of June and in early July. The animals appear in rather low abundance and lay eggs singly or in small groups on the lower leaf surface (observation Axel Hofmann).
Endangerment factors:
In the French Alps, Zygaena brizae is endangered due to the preference of habitats at medium altitudes by the following factors: intensification of grazing on the one hand with too much livestock, but also abandonment of grazing and subsequent reforestation on the other hand as well as housing development, especially construction of chalets (weekend and holiday houses) and roads/trails.
At lower elevations (eastern Europe) many populations are extinct or threatened by intensification in agriculture and forestry, also by housing developments of all kinds.
Remarks:
Zygaena brizae has an expansive Ponto-Mediterranean distribution and occurs mainly around the Black Sea, from eastern Austria and southern Poland to Central Greece (in Greece only locally in the mountains), Romania, Bulgaria and across Turkey to the Caspian Sea. Isolated from them another population group (ssp. vesubiana) occurs in the Southwestern Alps (especially southern French Alps, only very local and rare in the adjacent Italian Alps) in altitudes from 900m to 1700m above sea level.