GENEVA, Jan 20 (Reuters) - A record 103,000 Ethiopians and Somalis survived perilous trips across the Gulf of Aden to reach Yemen in 2011, double the number the previous year, the U.N. refugee agency said on Friday, despite violent upheaval in the impoverished Arab state.
It said more than 130 drowned during the crossings, in which migrants are often subjected to physical and sexual violence as well as extortion demands by traffickers. Three Ethiopians were killed by smugglers last week as they tried to escape.
"Most of the new arrivals reach Yemen's shores in desperate condition -- dehydrated, malnourished and often in shock," Adrian Edwards, spokesman of the United Nations High Commissioner for Refugees (UNHCR), told a news briefing.
Three out of every four arrivals were Ethiopians, mostly migrants seeking economic opportunities in Yemen or beyond, he said. "Ethiopian migrants avoid contact with the authorities as they look for ways to reach other Gulf states," he said.
Instability and a reduced police presence in Yemen -- where there have been months of deadly protests against the rule of President Ali Abdullah Saleh -- have given human traffickers and smugglers more room to operate, Edwards said.
"Reports of abductions of migrants or refugees upon arrival in Yemen persist - mostly for ransom or extortion," he said.
Somalis fleeing violence or drought in their famine-stricken homeland receive automatic refugee status in Yemen, which sits alongside key oil and cargo shipping lanes in the Red Sea.
Traditionally, Somalis and Ethiopians left for Yemen from Bossaso in Puntland in north Somalia, but migration routes have changed over the years, with many now leaving from Djibouti's coast, the International Organisation for Migration (IOM) said.
"Ethiopians who are leaving are coming from extremely rural areas where they feel that there is no other alternative but to risk the danger and try to get to Yemen and into the Gulf and other countries. So they feel that they are between a rock and a hard place," IOM spokeswoman Jemini Pandya told reporters.
(Reporting by Stephanie Nebehay; Editing by Mark Heinrich)