Our last day in the mountains. Mixed emotions really. We have made some great collections, enjoyed each other’s company (I hope), learnt a lot, had great support from our porters and field team and have been very lucky with the weather. We are a bit tired though and beginning to lose some of our enthusiasm. I even caught myself not being amazed at seeing a Quetzal so it is probably time for us to head home.

Oak forest at 8 in the morning, light streaming through the foliage

For me the highlight of the fieldtrip has been camping on top of one of the Cerros Tararias, almost certainly the first Europeans to have made it to the top of one of these 200 m high blocks of gneiss rock each with its mini paramó atop. Not only did we get the first plant collections from here but we also enjoyed spectacular views between Cerros Kamuk and Fábrega and down the valley of the Río Jet. A completely unexplored part of the Park and the focus of another trip should we get the funds.

View of one of the Cerros Tararias and out across to the Río Jet valley

Carlos ‘Leña’ and his son Josué. Carlos has been our guide and lead porter for much of our work in La Amistad Binational Park and has been a key player in our exploration of the Park.

It has also been a real privilege to be able to share some of what we have done and seen with visitors to the Museum as part of the Nature Live programme. For that a big thank you should go to Stephen Roberts and Jo Kessler from the Museum’s Nature Live team, Lee, Adam, Alex, Eddie, Ken and Tony from our Special Effects Department and Erica McAllister and Gavin Broad from our Entomology Department.

Also to Tom Simpson, who although was of course very lucky to come with us and whose feet in no way smell (no really they don’t), was incredibly professional and did everything possible to make sure that the live video links went well and answered as many of the questions on the schools blog as possible. Last but not least Jon from our Interactive Media team who has been assembling and editing this blog and to Grace from our Learning Programme who set up the events for schools.

Tom uploading his blog from the base of the Cerros Tararias

Our camp at the base of the Cerros Tararias

The plan today was to walk from our main camp at the Albuerge (see the map on Tom's blog) at 2,500 m to a smaller one, Casa Coca, at 1900 m so that tomorrow morning we can get back to the park entrance in good time for the eight hour drive back to San José. It was a beautiful sunny morning, the light streaming through the trees as we set off.

The plan was to interrupt our walk and sneak in a sample point half way, in the Pacific drainage. It was really amazing how dramatically the forest changed once we had crossed the main pide between the Caribbean and the much drier Pacific, the understory becoming more open and the canopy lower, possibly because of less rain and more wind?

Holger at the Continental pide collecting a sneaky lichen from the back of the Park sign

Scientifically the trip has been a great success, Jo Wilbraham made about 340 moss collections, Holger Thues about 500 lichen collections and Daniel Santamaría (from Costa Rica), Neil Brummit and myself about 640 vascular plants collections.

I think that Holger has certainly been the most enthusiastic about his finds with new records not just for Costa Rica but the whole of Tropical America. We are quietly confident of having collected some new species but will need to wait until we get back to a herbarium to be sure. This highlights the importance of global reference collections, such as our own, to identifying new species.

Jo with the bulk of our collections, bagged up and ready to be transported
to the INBio herbarium for drying, sorting and identification

It is 7 pm and I am in my sleeping bag as it is already really cold. Today we walked from our temporary camp where we spent last night up to our main camp in ‘El Valle de Silencio’ at 2,500 m. At this altitude we are in oak forest where the trees are up to 50 m in height, festooned with epiphytes, lichens and mosses and with a groundstory dominated by bamboo.

Oak tree with Tom Simpson of Nature Live for scale

View of oak forest interior

It occurred to me as we were walking through the forest that a surprising number of the trees we were seeing would be familiar in a forest back home: oak (Quercus), alder (Alnus), holly (Ilex), buckthorn (Rhamnus) and Cherry (Prunus), not the same species of course, but the same genera.

Quercus costaricensis

Rhamnus sp.

As I sit huddled in my sleeping bag I realise that there is a certain affinity with the climate back home too and also a physical one as many of these species, or at least their ancestors would have come from North America at a time when there was a land-bridge between our Continent and North America. So presumably these high elevation forests were colonised by trees coming from North America rather than South America, a phenomenon documented already by several authors.

I have just finished doing a videoconference with a group of schools who will be following our field trip to the Talamanca Mountains in Costa Rica next week. It was really fun and as usual we had some very good (and difficult) questions.

The plan is that we will share our scientific field work, which to be honest is one of the must fun parts of our work at the Museum, with the public and a pre-arranged group of schools. We will be running Nature Live sessions from the forest using an Inmarsat video satellite link, which will let us talk to visitors in the Museum's Attenborough Studio.

As well as blogging about the trip we'll also be answering the questions of teachers and school children who have been invited to sign-up for our schools link. If you know any teachers who might want to get involved and get access then please get them to contact Grace from the Museum's Learning Programme by email (videoconferencing@nhm.ac.uk).

So, we leave here Monday morning and by Wednesday we should be collecting our first moss, lichen, algae and plant specimens!