My last blog was written in July. The College has changed from mid-summer into autumn since then.
There have been several new sightings of species in College, but there have been no confirmed sightings of the fox cubs since they left College in the spring. We have occasionally seen the dog fox but, despite a new fox hole in the woods near the glade, he has not been seen regularly since the spring. Foxes do tend to move around quite a bit, so hopefully we will see them both back in College again soon.
The main sighting this summer has been a Badger (Meles meles). It has been seen twice; once at 2.58am on 23rd July by our porter, Ian Gilchrist, and there was another sighting of the badger on 29th July with Jake Moscrop. The badger was seen (thank goodness for CCTV!) leaving the College by going under the Lower Park Street gates and it was seen for the second time in the same area. The nearest badger setts are in St John’s and Churchill and so perhaps it was a young male foraging. They do travel far to forage, 2k is a good distance for this. There have been no sightings since then, but there have been lots of snuffle holes around that side of College and on 11th September I found a badger latrine – a hole where a badger had recently defecated. They tend to do this on the edges of their territory, so I think we can say that Jesus College now has a badger on site. Foxes and badgers can coexist, even though badgers are more dominant.
My favourite sighting this summer was of a butterfly, the White-letter hairstreak (Satyrium w-album). It was sitting on the grass between North Court and Maintenance, and when it eventually flew off (I got too close with my camera) it flew towards the Buckthorn trees outside North Court. I didn’t get very good views, but they were good enough to identify the large white ‘W’ on the outside of the hindwing. I have never actually seen this species before and so it was a lifetime tick for me as well as being new for the College. Other Lepidoptera sightings have been more reports of the Box-tree moth (Cydalima perspectalis). I haven’t had the moth trap out since lockdown, but I have seen this moth several times on the roof of the Library Cloisters. All three colour shades have been seen, the white, striped and dark forms of this moth. I have looked at the box in College but have not seen signs of any caterpillars (yet).
One new beetle for the site was the tiny beetle seen on the Dogwood in Library Court. This turned out to be the Bruchidius siliquastri; a recent (2014) introduction of the species to Britain. There were about 30 of them seen on the one Dogwood plant, about 40 feet from a Judas tree on the other side of the court. This beetle lives in the pods of Judas trees. I also found several Viburnam beetles (Pyrrhalta viburni) on the Birthwort plants in the Fellows’ Garden. I wonder if this beetle is responsible for the small holes that have appeared in the Birthwort (Aristolochia clematitis) leaves this year.
The Willow emerald damselflies (Chalcolestes viridis) have been seen around the pond and Jesus Ditch and I have seen several pairs mating on the vegetation overhanging the pond.
The young Tawny owls (Strix aluco) have been seen a few times this summer, and I have also seen what is probably an adult on a couple of occasions (the young begin to look very like the adults towards the autumn and so it can become difficult to tell them apart). Other bird news is that our Stock doves (Columba oenas) fledged at least two chicks this year. We don’t know if the Sparrowhawks (Accipiter nisus) have nested in the College grounds this year, but we have seen them flying over College several times and we have also seen several signs of them feeding here too.
The corvids are digging up our lawns again for chafer grubs. The Crows (Corvus corone) were seen digging up the lawns in Chapel Court on September 4th, and the Jackdaws (Corvus monedula) were seen digging in Second Court on 14th September.
I have started searching for Oak galls this year; it is apparently a good year for them. Plant galls are ‘abnormal growths induced by the presence of another organism living in or on the host plant and causing its cells to enlarge and/or multiply to provide both food and shelter for the gall-causer’ (Britain’s Plant Galls; a photographic guide by Michael Chinery, 2011). The presence of these galls on our oaks indicates the presence of specific gall-causing invertebrates and so we can add a few more species to our species list. The most common gall seen on most of our oaks is the Knopper gall and this is induced by the gall wasp Andricus quercucalicis. The Common Spangle gall is caused by the gall wasp Neuroterus quercusbaccarum; the Ram’s-horn gall is caused by the gall wasp Andricus aries and Cola nuts by Andricus lignicolus. Our Walnut tree by North Court is infected by the gall mites Aceria erinea and Aceria tristriati. There are Cecidophyopsis psilaspis and Taxomyia taxi on several of our Yews. I have made a new Page for Plant Galls under the species lists and hope to add to this list in spring.