Spain for one month

So maybe a week or so in May and then most/all of June. Is that a good time for birding in Spain?

What places do you want to visit? If you are concentrating on the north, then you may want a car for at least most of the trip, whether the itinerary is planned in advance or spontaneous. I'm told Bilbao is better without a car, but if that's only 2-3 days of your 4-5 weeks, parking it would be a minor consideration. My understanding (I've checked into this a lot because I'm interested in visiting the Basque country and Galicia) is that train and bus service is not very efficient. Maybe there aren't even many places you could rent and drop off a car once you are away from the main cities. I've also seen recommendations on the forum to lease instead of rent if you want a car for a month.

You could fly into Barcelona, get the car and go up the coast and then through the Pyrenees, then the north east (and if you have time, northern Portugal) and drop the car in Madrid and fly out from there.

Take a look at visiting Navarra for a few days. They have the The Birding Navarra network. Birding Navarra is a theme club created by the Government of Navarra's Tourist Image and Promotion Service to promote and develop ornithological tourism in our community (their description).

About 30km east of Pamplona is the gorge of Lumbier, and I often visit there with my work and it is quite common to see birdwatchers visiting the gorge.

From my understanding, some of the best bird-watching in Spain is in the Extremadura region, specifically the Parque Nacional de Monfragüe, which was designated a Special Protection Area (SPA) for Bird-Life by the European Union.

Here is some info from the park's website, translated into English:
"Monfrague is an outstanding site for birds of prey, with more than 15 regular breeding species. including the world's largest colony of Eurasian black vulture (over 200 pairs), it has the world's highest concentration of imperial eagles (more than 10 pairs), a large population of griffon vulture, and several pairs of Spanish imperial eagle, golden eagle and Bonelli's eagle..."

Sounds like it may be up your alley? :)

One could do a nice little road trip from Madrid to Sevilla through Extremadura, which is full of time-warped old towns, castles, monasteries, and beautiful countryside. (and not to mention bird-watching). I would do something along these lines:

Start in Madrid, drive to

-Day 1: Cáceres: The old town of Cáceres is a UNESCO World Heritage Site and has a mix of Roman, Islamic, Gothic, and Renaissance styles.

-Day 2 and 3: Parque Nacional de Monfragüe: Day trip from Cáceres to this biosphere reserve, includes stunning cliffs and rock formation, plus many kinds of wildlife (especially noted for its Griffon vultures). Has some really great hiking trials including government-built hides for Bird-watching. I would spend two days here, based on your interests, day triping in from Cáceres

-Day 4: Trujillo: This town is where some of Spain’s most famous(infamous) conquistadors came from. The town has a few baroque and Renaissance palaces and an interesting Museum of Francisco Pizarro, who led the expedition that conquered the Inca Empire.

-Day 5: Guadalupe: Has the beautiful Real Monasterio de Guadalupe. You can tour this monastery and its collection of art, jewels, illuminated manuscripts. You can also see two cloisters, one late-14th-century Mudéjar, the other Gothic.

-Day 6: Mérida: Also a UNESCO World Heritage site with some of the best preserved Roman ruins in Spain, including bridges, villas, aqueducts, theaters, temples and everything in between.

-Day 7: Zafra: On the way to Zafra stop by Castillo de Feria, an originally Moorish hilltop fort. Zafra itself is a white walled town nicknamed "Little Sevilla" and feels very "Moorish". The filmed some scenes from the T.V. show Game of Thrones here.

-Day 8: Jerez de los Caballeros: A very picturesque small town. The old town is surrounded by a Moorish wall with six gates. After it was conquered from the Moors, the town was transferred to the Knights Templar, who left their own architectural mark.

-Day 9: Monesterio: Finish your trip at Monesterio which is an unassuming little town that produces some best jamón ibérico de bellota in all of Spain. You can find the real Museo del Jamón there, not those touristy ones you will find in Madrid.

Drive to Sevilla

Carlos mentioned some great places to visit that are frequently overlooked by visitors, and the National Park could easily be fit into your timeframe. There are a number of historic sites with Celtic round houses in Galicia. Some places we enjoyed in that area: Santiago de Compostela, Muxia, Sanabria, Cabo Ortegal, Praia de aquas Santas (cathedral beach), Betanzos, Ponferrada, Alto de Cebreiro, church of San Salvador in Vilar de Donas, and Santa Maria de Leboreiro. Further east, Picos de Europa park, Cangas de Onis, Sanctuary of Covadonga, Getaria, and Zumaia. For larger towns, Burgos, Leon, Zamora, and Salamanca. The more you research, the more places you’ll find that you want to visit. For many of the places I mentioned, a car is essential. Driving in Spain is like driving in the states. Roads are well marked and in good repair. If you want to stay off the autopistas/interstates to see more scenery, there is usually a “nacional” N road nearby that parallels it. The N roads were the main roads before Spain had many interstates and go through all the small towns the interstates bypass.

Thank you for these great ideas!

It will be hot in southern Spain, but there is a national park near Madrid with flamingos.

I've no bird-watching experience and, in particular, don't know about seasonal changes. But I've often heard Valencia described as a major bird-watching region with coastal wetlands, steppes and mountain terrain. There are also many interesting sights in the region (including in Valencia city), and it's the home of paella. Of course it's not convenient for north-west Spain, but you could do a loop drive heading south from Barcelona before going diagonally to Galicia.

Thanks again, everyone.

I just booked a flight in and out of Barcelona for 5 weeks. It was very reasonable to rent a car for the duration, this way we will make a big loop through the country, focusing on many of the good birding areas. Of course we will also stop at many of the interesting villages and spend a small amount of time in the larger cities.