site 0017 description

0017: Jivero 2, Cueva de
Ozana 30T 453618 4794705 (Datum: ETRS89. Accuracy code: G) Altitude 250m
Length 517m Depth 9m
Area position : Site entrance in context : Logbook search

Updated 13 February 1998; 5 December 1999; 16th September 2000; 6th May, 7th October 2001; 1st June, 12th October, 6th November 2003; 25th September 2008; 19th March 2009; 1st February, 1st October 2011; 19th September 2012; 18th April, 6th September, 20th November 2013; 7th September 2014; 12th October; 29th November 2016; 19th May, 29th August 2017; 20th September 2018; 11th May 2019; 3rd September, 10th October 2022; 6th May 2023; 8th February, 24th April 2024

A through trip, popular with families with young children. A climb up from a pool into the bottom entrance immediately enters a superb phreatic tunnel containing the stream. A sandy gallery on the right soon closes down. The walking-size streamway continues to emerge at the twin openings of the upper entrance.

The following fauna is listed by Notenboom (AX): Echinogammarus/Gammarus, Cyclopoidea, Prosobranchia/Hydrobioidea,Proasellus ocul., Ostracoda, Pulmonata/Basommatophora, Bivalvia/ Sphaeriidae, Insecta, Oligochaeta and Nematoda.

Also Ortiz (AM) records the following crustaceans: Asellus coxalis ssp. and Gammarus berilloni Catta. The crayfish (Austropotamobius pallipes) were particularly abundant during 1999 and 2000 and care should be taken when passing pools of water. In 2008, 12 individuals (one here) were noted from 2cm to 5cm long with no more than 3 in a pool, although in February 2009 none were detected and a month later only 2 seen. A short video of the crayfish with photos was put together at Easter 2013.

In early August 2013 only Austropotamobius pallipes were seen in the cave but, 2 weeks later, signal crayfish (Pacifastacus leniusculus) were reported. Signal crayfish were also observed in Cueva del Agua in late July. The signal crayfish in Cueva del Agua were reported to the Medio Ambiente in Ramales; this was before the specimens in Jivero were seen. A visit in November 2013 noted apparently healthy Austropotamobius pallipes and no signal crayfish. In July 2016, "giant crayfish" were seen. In August 2022, a number of signal crayfish were observed.

At Easter 1996, it was recognised that, along with the remains of an old mill in the depression between Cuevas de Jivero 2 and 3, slots in the wall of the downstream entrance to Jivero 2 indicated the use of a possible wooden-boarded dam and / or an overshoot mill wheel. There is also a wall built about 15m inside the top entrance.

At Easter 2001, a number of side passages were looked at that may not be on any survey. These need tying in with both the Spanish and British surveys.

On a trip in the summer 2012, an aven was climbed near the top entrance and surveyed back to there. Animal scratchings were seen in this area.

In August 2017, several "native crayfish" were seen and many fire salamander juveniles were spotted in a side passage near the entrance.

Members of the Matienzo Karst Entomology Project carried out spot sampling and netting over Easter 2019. Photos were also taken.

The cave was completely re-surveyed in November, December 2023, and the new survey (with site 1111) published early 2024.