as $53 million in undrawn credit and lending facilities. Granteer generated oil sales of $187 million, an increase of 25% from the second quarter of 2025 and 9% from the prior quarter. The year-over-year increase was primarily driven by stronger Brent pricing, partially offset by lower sales volume and higher quality and transportation discounts in Colombia associated with the alternative transportation routes with the Colombia-Ecuador border closed. Sequentially higher rent prices, lower Columbia differentials, and stronger premiums equity were more than offset the impact of lower sales volumes from having only one lifting during the quarter and higher royalties associated with stronger commodity prices. Total operating expenses decreased by 22% to $52 million compared to the prior quarter and decreased by 7% compared to the second quarter of 2025, primarily due to lower work over activity, reduced field personnel costs, and inventory fluctuations. As we move through the second half of the year, our priorities remain with allocating capital with discipline, protecting liquidity, generating free cash flow, and using our financial flexibility to reduce debt and invest in the highest return opportunities across the portfolio. The actions completed during the quarter leave Grand Tierra with a more focused portfolio and a stronger foundation to further contribute to long-term shareholder value. I'll now turn the call over to Sebastian to discuss some of the operational highlights.
Thanks, Ryan, and good morning, everyone. From a production perspective, Grand Tierra delivered second quarter 2026 average working interest production of approximately 41,500 barrels of oil per day, which was within our annual guidance range and reflected the impact of the Canadian asset dispositions completed during the first half of the year. Production was 9% lower than the prior quarter and 12% lower year-over-year. The decrease primarily reflected the Canadian dispositions in temporary unplanned artificial system failures at Accordionero and Coimby, partially offset by strong performance from the Conejo discoveries, early water flood responses in Chenange and incremental production from the Perico block. From an operational standpoint, as Ryan noted, during the quarter we completed our $123 million capital-carry commitment under the Surriente joint venture with Ecopatrol through the completion of the six-well development drilling program at Coimbi, which was successfully delivered under budget. In Tisgarama, execution has already begun with licensing, surveying and detailed engineering of flowlines, facilities and wells. We expect to initiate field activities in the second half of 2026, which will include well workovers, flowline installations and new facilities. In Ecuador, we received government approval for three additional field development plans covering Chirapa, Conejo and Perico, bringing total approvals to five of our six discovered These approvals allow us to transition the portfolio from exploration toward development while retaining approximately 156,000 acres for 20 years with an additional approximately 16,000 acres at Espejo pending approval. Ecuador production averaged 7,990 barrels of oil per day during the quarter, supported by the continued strength of the Conejo discoveries and an earlier than expected response to water injection at Chenange. These results further reinforces our confidence in the application of water flooding across the portfolio to significantly improve overall production performance and project economics. As Ryan highlighted, the lodgepole disposition further sharpened our Canadian portfolio. Our focus is now on Dawson Clearwater and Mount Head, where a new resource report highlights meaningful long-term exploration and development potential. McDaniel assigned best estimate 2C contingent resources of approximately 6.5 million barrels at Dawson Clearwater, along with unrest best estimate prospective resources of approximately 55 million barrels at Dawson Clearwater and 12 million barrels at Mount Head, representing approximately 67 million barrels of combined un-risked best estimate prospective resources. Prospective resources relate to undiscovered accumulations and will require confirmation through future drilling. Grand Tierra operates both plays with a 100% working interest across approximately 108,000 net acres. Dawson Clearwater benefits from shallow depths and low cost horizontal multilateral development, while Mount Head targets light oil and broadens our commodity mix in Canada. Both plays are also suited to water flooding and are expected to be a focus of our 2027 drilling activity. Overall, the quarter reflects disciplined execution across the base business and continued progress in building a more focused, durable, and opportunity-rich portfolio. I will now turn the call back to the operator, and Gary, Ryan, and I will be happy to take questions. Operator, please go ahead.
Operator
Thank you. Ladies and gentlemen, we will now conduct the question and answer session for securities analysts. If you have a question, please press the star key followed by one one on your touchtone phone. You will then hear an automated message advising your hand is raised. Your questions will be pulled in the order they are received. Please ensure you lift the handset if you're using a speakerphone before pressing any keys. One moment please for your first question. Our first question comes from the line of Joseph of Schachter with Searcy. Your line is now open.
Good morning, Gary, Ryan, and Sebastian. First thing, congratulations on surfacing the value that you've created and a 52-week high for the stock, so the market likes what's going on. I know we can't talk about South America, but can you talk about the go forward? You mentioned, of course, the Clearwater and the commentary. Sebastian covered that also the glock potential are we looking at canada where you're going to increase the budget in 27 materially is there going to be mna around these certain areas is there going to be a big portion of the budget for water floods can you kind of give us an idea of what you might do in canada and then also in in azerbaijan how much money might be spent in 2027 and how do you see international going forward yeah good morning Joseph and thank you for Canada we're quite excited as both Sebastian and Ryan outlined in the
Clearwater we have a clear runway and we we've consolidated land and we we are putting together our program our continuous program going forward Mount Roundhead is a region we just acquired the land, and we're quite excited about it as It worked with vertical wells, and we're going to try it with horizontal wells. So we're quite excited about both, especially being light oil. Azerbaijan, I think, is very exciting for us because we're starting to shoot gravity over the summer here. And our plans are to drill two wells next year, two wells in an area that's very prolific in terms of oil and gas. As you know, the gas has quite a great value in the country. And so we're going to focus a lot of effort. We're also working on a couple of joint studies on existing fields with the government. And we'll progress those over the next uh coming months going forward so it it's possible that uh we could be looking at some exploitation projects in azerbaijan as well so quite excited about the the go forward future of the company do you have a any more ambition internationally outside of azerbaijan certainly we we always look and we have very specific criteria as a company we look at and And we're basin-driven. And so if there are opportunities for shareholders going forward, we'll certainly look at that, but not anywhere. It has to be countries like and basins like Azerbaijan or Western Canada. Super.
Okay, again, thanks very much for answering my questions, and congratulations for surfacing the value. A nice reaction in the market today.
Operator
Thank you. Our next question comes from the line of Jamie Somerville with Roth Capital Canada. Your line is now open.
Congrats, Gary. I'm just wondering, with regards to the lodgepole's disposition, did that include any production reserves or contingent prospective resources? yeah it's about it's about 850 barrels a day that's come off but it also took out a bunch of the aro so you'll see in the press release that we've added all that out so actually a benefit to the company perfect thank you and then um how do you think the transaction might impact your gna Like, do you have a GNA guidance for run rate for post-transaction?
Go ahead. Yeah, I think, you know, as we get closer to closing, we'll provide more guidance on 2027 plans and, you know, future financial projections.
Operator
Gentlemen, there are no further questions at this time. Please continue.
I would like to thank everyone once again for joining us today. We look forward to speaking with you over the next quarter. update you on our ongoing progress thank you very much this concludes today's conference thank you for your participation you may now disconnect