Centro de Investigaciones Científicas de las Huastecas "Aguazarca"
Calnali, Hidalgo, México
Member, Organization of Biological Field Stations

CICHAZ cell phone:
From the US: 011 52 (771) 200-4204 
From México: 045 (771) 200-4204

Download the most recently updated CICHAZ GUIDE here!

Welcome to CICHAZ! We hope you have a fun, safe, and productive stay. Common sense applies. If you break something, use something, or get something dirty, please fix it, replace it, or clean it up.

We operate the field station out of a rural residence in a remote area of rural Mexico. Keep in mind that there is only a minimal first-aid clinic in Calnali, and only marginally better care in Zacualtipán and Huejutla, each over an hour away. The nearest good hospitals are in Pachuca and Tampico, 3 ½ and 4 hours away, respectively. Make sure you have appropriate medication/training for any conditions or allergies you have. The facilities we operate do not conform to U.S. or any institutional safety standards. By working, visiting, or volunteering at CICHAZ, you assume any and all risks and responsibilities and release the owners and users of CICHAZ, as well as their employers and affiliated institutions, from any and all liability.

By bus and taxi:

From Mexico City's Terminal Norte, there are occasional Estrella Blanca second-class (unairconditioned, slow) buses to Calnali, about 5 hours, for about $120 pesos. There are also frequent Estrella Blanca buses to Huejutla and Molango, both of which stop in Molango (about 4 hours) where you can take a taxi into Calnali ($300 pesos, another 40 min). Taxis stop running in the late evening.  From the Mexico City airport, the easiest thing to do is to take a first-class airport bus to the Pachuca bus terminal ($170 pesos) and then catch one of the aforementioned buses north, although they often fill up in Mexico City and you may have to stand for a while. The bus passes right by CICHAZ before entering downtown Calnali; ask the bus driver to look out for the bougainvilleas on the left hand side after crossing the bridge before Calnali.

You can also make arrangements for a Calnali taxi to pick you up at the Pachuca bus station ($700).  

From Tampico, there are several first-class ADO buses from the downtown ADO terminal to Huejutla several times a day (4 hours, about $200 pesos). From Huejutla, there are 1 or 2 combis (minibuses) to Huejutla. You can also take a taxi from Huejutla to Calnali (about $500).

From Cd. Valles, take a bus to Tamazunchale and then ask for directions to the Huejutla bus stop; there are buses for about $50 pesos that take about an hour and run every half hour. Follow directions from Huejutla as above.

By car:

General tips for driving in Mexico

On rural roads, a left turn signal usually means "pass me", unless the car is slowing down,  and a right turn signal means "do not pass". When turning left, do not use your turn signal; slow down and stick your arm out the window to indicate a left turn.

Slow down for topes (speed bumps) through towns and small settled areas.

Be on the lookout for washouts and rockslides. Branches on the ground and red cloths on vegetation mean there's danger ahead, as do hazard lights on the vehicle in front of you.

Gas is available in several places in and around Calnali, including Miguel’s across the street, sold out of 20-L jerrycans at a slight markup. The gas is fine, but it's cheaper and more convenient to try and fill up in Molango, Atlapexco, or Huejutla.

Directions from Tampico, College Station, Brownsville, McAllen, and points northeast:

Follow signs to Pánuco, Veracruz.  At Pánuco, head south towards Tempoal (recommended: El Palenque restaurant on east side of highway), then bear southwest towards Huejutla.  Gas up in Huejutla, as it’s the last real gas station before Calnali. It’s slightly over an hour to Calnali.  Follow signs out of Huejutla towards Mexico City and Pachuca . Right after leaving the built-up area of Huejutla, turn left towards Atlapexco. Immediately before Atlapexco, turn right onto bypass road towards Yahualica.  Keep going straight through Tlalchiyahualica and Mecatlán (do not turn uphill towards Yahualica).  You’ll go over a bridge after Mecatlán, and the kilometer markers now count down to the Calnali turnoff.  There are frequent rockslides on this road, so be careful.  Pass the town of Calnali , on your right, and both turnoffs for Calnali/centro.  CICHAZ is on your right about 100 m after the second turnoff.

By car from Cd. Valles, S. L. P., Monterrey , Laredo , and points northwest:

Drive south on federal Highway 85 to Tamazunchale; right after the bridge, turn left towards S. Felipe Orizatlán. Bypass S. Felipe Orizatlán, then turn right towards Mexico City/Pachuca before you enter Huejutla.  The bypass road will cross Hwy. 105; keep going straight towards Atlapexco and follow directions above.

By car from Tuxpan, Veracruz port, and points southeast:

From Álamo , Veracruz , follow signs to Chicontepec.  At Benito Juárez, keep going straight on towards Atlapexco and Huautla (do not turn towards Chicontepec). The last gas station is right before Atlapexco.  Keep going straight towards Atlapexco, and stay on the bypass road to the right of the town of Atlapexco .  Immediately after passing the town, turn left towards Yahualica and follow directions as above.

By car from Mexico City , Pachuca , and points south and southwest:

Take Hwy. 105 north through Zacualtipán. There can be dense fog from this point on.  Gas up in Molango.  Right before Ixtlahuaco, turn east (downhill) towards Calnali. After about 20-30 min, you’ll cross a bridge over the Río Calnali (Calnali-mid). CICHAZ will be on your left next to the Vidrios y Aluminio sign.  

By donkey from Pochutla:

The donkey knows where to go.

• Key sets are hanging on a hook in the main dining room. Each has four keys. One goes to the front door, another to the garage door, one to the fish room, and one to the back door.
•  The door to the second floor deck has a padlock that can only be unlocked from inside the house. Be careful not to lock yourself out when you go on to the deck – it happens!

CICHAZ policies, guidelines, and survival guides

1. We operate the field station out of a rural residence in a remote area of rural Mexico. Keep in mind that there is only a minimal first-aid clinic in Calnali, and only marginally better care in Zacualtipan and Huejutla, each over an hour away. The nearest good hospitals are in Pachuca and Tampico, 3 1/2 and 4 hours away, respectively. Make sure you have appropriate medication/training for any conditions or allergies you have. The facilities we operate do not conform to U.S. or any institutional safety standards. By working, visiting, or volunteering at CICHAZ, you assume any and all risks and responsibilities and release the owners and users of CICHAZ, as well as their employers and affiliated institutions, from any liability.

The neighborhood, Aguazarca:

2. We strive to be an integral part of the local community. We are fortunate to have great neighbors who help keep CICHAZ secure and running smoothly. Patronize local businesses as much as possible. Neighborhood kids will often come into the living/dining area after school and on weekends to play. There is a small, growing library of children's books; each kid can take one book home at a time and has to bring it back before taking another. Contribute Spanish or Spanish/English kids' books if you can, and feel free to leave grown-up books/magazines behind if you're done reading them.

3. Clemente and Irma Hernandez, and their children Ricardo, Osvaldo, Heriberto, and Yesica, are the primary caretakers of CICHAZ. They live across the street directly in front of the Taller de Vidrios next door. Ask them for help with anything you need. At the end of your stay, please give Irma at least $150 pesos to clean the house and launder sheets/towels for the next occupant.

4. Carla and Rey and their children Diego, Miriam, Mariana and Yasmin, next door at the Taller de Vidrios and Abarrotes San Antonio, sell dry goods, milk, fruits and vegetables, fresh tortilla dough, beer, and occasionally marinated meat. For ultimate convenience, call out to Carla from the kitchen window and she will bring you what you need. Rey can do any metal or glass work you might require. Ernestina is the older lady next door on the other side of the house.

5. Try to balance beer purchases between Carla and the woman across the street (Miscelanea Nelly). In either case, you will have to pay a deposit on the bottles, which you'll get back upon returning them.

6. About 100m down the street towards Calnali, there are excellent tacos al pastor most evenings on the right hand side.

The house: 

7. Common sense applies. If you break something, use something, or get something dirty, please fix it, replace it, or clean it up.

8. Upon arrival at CICHAZ, go up to the roof and open the valve to the natural gas tank, then light the pilot on the hot water heater. If you're keeping aquatic creatures, turn on the water to the dechlorinated water reservoir and treat with 35 ml Amquel once it's full.  When you leave, be sure to turn off hot water heater, gas tank, and water to reservoir.

9. Fuse box is on front of the house and breaker may have to be turned on to get power. Extra fuses are in kitchen, please replace with identical fuses from hardware store in town. Power is "dirty" and fails occasionally, so bring voltage regulators if working with delicate equipment. A headlamp is a great accessory to have.

10. Tap water is chlorinated and fine for brushing teeth, but don't drink it. Carla sells 40-L canisters of drinking water for 12 pesos plus deposit. White PVC taps in fishroom and interior lab room produce dechlorinated fish water from the rooftop reservoir. Please conserve water as much as possible. Supply can be intermittent. The black plastic reservoir on top of the roof is filled intermittently, and we have gone up to 48 hours without running water.

11. Try to urinate in the garden rather than in toilets. Put toilet paper and other sanitaries in trashcans rather than down the toilet.

12. Turn gas off to stove when not in use.

13. Wash clothes in washing machine, then hang on second floor terrace to dry.

14. Make sure Clemente and Irma know about any perishables you leave in the fridge on departure.

15. Leave all lab and fishroom areas as you found them on arrival.

16. Sheets, towels, and blankets are on second floor landing. When you leave, pile sheets and towels in washing machine and, if necessary, pay Irma to do extra loads/hang up clothes.

17. Check shoes and drawers for tarantulas and scorpions.

18. For details on research equipment, see Facilities.

The garden:

19. There is a nest of Africanized honeybees about halfway to the river and on the left. Don't bother them.

20. Introduced fire ants are a pest here just like in Texas. They are merely annoying unless you are allergic.

21. There is an abrupt dropoff to the river, exercise caution with young children or impaired adults.

22. Help yourself to firewood, fruits, and vegetables. We have countless citrus trees as well as mangos, avocados, and bananas. Be sure to try the pomarosa (rose-flavored fruits in season in May/June) near the path to the river.

23. Don't remove any fish from this stretch of river, as this is our long term study population.

Ecological effects of an introduced cichlid, Archocentrus nigrofasciatus, on native Mexican cichlid communities

The convict cichlid, Archocentrus nigrofasciatus, is a popular species in the aquarium hobby, due largely to its hardiness and ease of breeding in captivity. These traits also increase its chances of establishment when introduced in non-native environments, and many established nonindigenous populations have been reported. A relatively recent introduction of A. nigrofasciatus from an aquarium breeding facility has led to its establishment and spread in the Río Pánuco basin in northeastern Mexico . The ecological effects of this species in Río Pánuco communities have not yet been examined, but there appears to be a decline in the native cichlid species where it is present. My main interest is to study interactions of A. nigrofasciatus with native Herichthys cichlid species. I will compare resource use and nesting habitats of native Herichthys species in areas of sympatry and allopatry with introduced A. nigrofasciatus. This will allow me to examine niche overlap and niche shifts in native Herichthys species where they co-occur with A. nigrofasciatus. Additionally, I will compare diet and habitat use of A. nigrofasciatus in Río Pánuco communities with data from its native range in Costa Rica .

This study will provide much needed information on the extent to which this introduced species may compete with native cichlids for resources. In future studies, I hope to add to this research by testing hypotheses about the interactions of these species experimentally.