The UK's largest onshore wind farm project will create fewer jobs than forecast, according to a report for a bird conservation charity.
The RSPB report is disputing the jobs benefits to Lewis
The Royal Society for the Protection of Birds (RSPB) said its study has found that "at best" the Lewis Wind Power (LWP) project would support 70 jobs.
LWP defended research carried out on its behalf that claimed 233 posts would be created once the site was working.
The company proposes to build 181 wind turbines on Lewis in the Western Isles.
RSPB Scotland commissioned global real estate adviser DTZ Consulting to carry out an economic assessment of the plan for Barvas Moor.
The charity has previously opposed the development because of its fears about birds flying into the turbines.
Stephen Lucas, DTZ director of economics, said the scheme posed a potential threat to tourism.
He said: "The developer claims that over 230 jobs will result from the wind farm and various payments to landowners and the community.
"Our own assessment is that the development will support at best around 70 jobs in the Western Isles."
Mr Lucas added: "Factoring in the potential harmful effects on tourism - which the developer has not attempted to do - could mean that the LWP project could result in a net negative impact on the local economy."
LWP is a 50/50 joint venture by engineering group Amec and British Energy Renewables.
David Hodkinson, LWP director, said: "We look forward to studying the contents of the report, but do wonder why RSPB is having to broaden its campaign against the Lewis Wind Farm away from the bird interests that are at the heart of its charitable status and Royal Charter."
"The economic development reports accompanying our proposal have been assessed by a number of bodies and organisations with economic development expertise."
He added: "We note that the work commissioned by the RSPB stands alone in disagreeing with our assessment that the Lewis wind farm would bring strong economic benefits to the Outer Hebrides."
A study it commissioned by Regeneris Consulting found that the 233 new jobs would be on top of those supported during the construction phase.
It also claimed that many other posts would be created, or supported, indirectly.
The RSPB said the DTZ report had been backed up by a leading Scottish economist and former technical advisor to Western Isles Council.
Strathclyde University's Emeritus Professor of Economics Iain McNicoll described the original Regeneris view as "rose tinted".
He said: "DTZ's critique of Regeneris's report is fundamentally valid, and though harsh is not unfair: important policy decisions are influenced by this type of work, and hence it is important that it is done well.
"Significant errors in both method and calculation made by Regeneris are correctly identified, and DTZ's own analysis, though handicapped by non-access to data, etc., is superior."
Comhairle nan Eilean Siar (Western Isles Council) backed the scheme, despite receiving more than 4,000 objections.
Last month, LWP unveiled revised plans, scaling down the development from the 234 turbines originally planned to 181.