Bupleurum kakiskalae is endemic to Crete, Greece. This species occurs in five locations with an area of occupancy (AOO) of 20 km² and an extent of occurrence (EOO) of 57 km². The number of mature individuals is estimated as 50–300. Extreme fluctuations in the number of flowering individuals are observed from year to year but currently there is no evidence for a continuing decline. The species is assessed as Endangered based on criteria B and D (EN B1ac(iv)+2ac(iv); D).

Bupleurum kakiskalae is endemic to the island of Crete, where it is known to occur in the mountain range of Lefka Ori on the cliffs. There are six distinct localities known: Kakiskala, Kalokampos, Petrade, Avlimanakou, Malemou and Zaranokefala (Thanos et al. 2015, A. Kaltsis and K. Koutsovoulou pers. comm.).

Only two localities were known for this species, until recently. More intense field surveys carried out during the last 15 years led to the discovery of four new localities (Kaltsis et al. 2013, Thanos et al. 2015,  Kaltsis A. and Koutsovoulou K. pers. comm.). In four localities (Kalokampos, Petrade, Avlimanakou and Zaranokefala) most of the plants occur on inaccessible cliffs and can be observed only with a telescope or binoculars. Considering that a very low number of individuals are found in the wild and that the plant flowers only once during its lifetime, only few individuals flower each year (estimated between 50 and 300, depending on the year) while the plants at vegetative stage are estimated to be fewer than 1,000 individuals. Annual monitoring of this plant's entire population is not possible due to the inaccessible areas where the species occurs. However, it is safe to assume that the whole population undergoes extreme fluctuations.

This perennial herb occurs in crevices of steep limestone rocks. Given that only a small number of individuals remain and the fact that the plant flowers only once during its lifetime, there are very few individuals which flower at the same time (depending on the year). Seed production and the establishment of seedlings is therefore extremely variable. It seems to have very strict ecological requirements.

The main threats facing B. kakiskalae are the low probability of genetic exchange within the population due to the small number of individuals flowering at the same time, and cliff instability, as the substrate on which it grows collapses periodically. Goats may also graze any accessible plant. A further threat is posed by rock climbing that leads to further erosion and habitat degradation.

The species is not utilized

Bupleurum kakiskalae is included as a priority species in Annexes II and IV of the Habitats Directive and under Appendix I of the Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention). It is listed as Critically Endangered (CR) B1ac(iv)+B2ac(iv);D1 in the Red Data Book of Greece (Fournaraki and Thanos in: Phitos et al. 2009), as well as in the IUCN Red List (Fournaraki and Thanos 2011). It is also protected by the Greek Presidential Decree 67/81.

In situ: a microserve of 1 ha has been established at Samaria gorge. The plant is included in a Natura 2000 site which gives it indirect protection.

Ex situ: the plant is cultivated successfully at the botanical gardens of the Forestry Department of Chania at the nearby village of Poria and at the locality Xyloskalo.

Actions Needed
Studies on the biology and ecology of this species must be continued to properly define the conservation measures needed.  Regular collection of seeds should be made in order to conserve the widest possible spectrum of genetic material.