Assessing the distribution & diversity of Kuril-Kamchatka abyssal plain & Okhotsk Sea deep-sea fauna

FORMER SPONGE RESEARCH IN THIS REGION 150 years of sponge sampling in NW Pacific Collections mainly from Russia & Japan 200 spp. distribution records collated from older publications and OBIS INTRODUCTION METHODOLOGY RESULTS DISCUSSION

NEW SAMPLING IN THIS REGION KuramBio and SokhoBio expeditions: Twenty-two stations were sampled Depths range from 1700-5500 m. Sponges were collected using an Agassiz trawl (AGT), Epi-benthic sledge (EBS), and box-corer (GKG). INTRODUCTION METHODOLOGY RESULTS DISCUSSION

TAXONOMY & DATA COLLECTION Collating North Pacific Ocean sponge distribution records Standard methodology INTRODUCTION METHODOLOGY RESULTS DISCUSSION

DIVERSITY & ENDEMISM >100% increase (20 spp.) Increases in the number of abyssal species in this sector of NW Pacific New to science species Endemism 29% spp. new to science (11 spp.) 55% spp. endemic (21 spp.) 26% increase (8 spp.) Kurile-Kamchatka Okhotsk Sea No. of Spp. 31 37+ 35% spp. endemic (11 spp.) 21% spp. new to science (3 spp.) INTRODUCTION METHODOLOGY RESULTS DISCUSSION

RARITY & ABUNDANCE X 8 more specimens from Okhotsk than KKT >60% species limited to 1 stn. X 8 more specimens from Okhotsk than KKT 19% of previously known species not re-found 74% hexactinellid Species rarity is common Hexactinellid abundance – often high in biomass >50% species limited to 1 stn. 83% of previously known species not re-found 43% hexactinellid INTRODUCTION METHODOLOGY RESULTS DISCUSSION

DEPTH RANGES DEPTH INTRODUCTION METHODOLOGY RESULTS DISCUSSION OKHOTSK SEA KURILE-KAMCHATKA DEPTH EURYBATHY 55% spp. eurybathyic 57% spp. eurybathyic SUBMERGENCE? 67% demosponge spp. eurybathyic <50% demosponge spp. eurybathyic >70% hexactinellid spp. eurybathyic >70% hexactinellid spp. eurybathyic INTRODUCTION METHODOLOGY RESULTS DISCUSSION

UNUSUAL NW PACIFIC ABYSSAL CHARACTERISTICS Dominance of demosponge species; not typically seen in abyssal fauna Carnivorous sponges (Cladorhizidae) dominate demosponge spp. & genera richness Global importance of carnivorous sponges 70% of spp. demosponges Cladorhizids: >50% of demosponge spp. 72% of spp. demosponges 15-20% of cladorhizids found in this NW Pacific sector Cladorhizids: 87% of demosponge spp. INTRODUCTION METHODOLOGY RESULTS DISCUSSION

CONNECTIVITY IN NW PACIFIC Okhotsk-N/NW Pacific = 45% East Kamchatka Current Strong connections found throughout abyssal NW Pacific sponge fauna Importance of straits & sub-Polar gyres & currents Strong abyssal connectivity found between semi-enclosed Okhotsk Sea and open NW Pacific Ocean: Hex vs. Demo KKT-N/NW Pacific = 65% Okhotsk Sea Gyre Aleutian - Okhotsk = 30% W. Sub-Arctic Gyre STRAITS Alaskan Stream Oyashio – Sub-Arctic Current Kuroshio – North-Pacific Current INTRODUCTION METHODOLOGY RESULTS DISCUSSION

PROCESSES DRIVING RICHNESS & ENDEMISM Sponge richness is potentially aided by: Isolation – Okhotsk 36 Ma Extreme environmental changes Productivity Low population densities Heterogeneity INTRODUCTION METHODOLOGY RESULTS DISCUSSION