MAYON?S rumbling sounds, its crater glowing at night, and snakes suddenly out of their pits.

These are signs that the volcano?s eruption is forthcoming, according to Margelita Lopo, who lives at Upper Cabangan in Camalig, Albay.

?We have been hearing rumbling sounds, witnessing the crater glow at night, and seeing snakes in our farm just next to the six-kilometer permanent danger zone,? she said.

But Lopo said she was still waiting for another sign: wells drying up.

Right now, she said, the wells ?are still filled with rain water.?

Animal behavior

Another Camalig resident, Adela Solano, 68, of Barangay Tinuburan, said that even before the Philippine Institute of Volcanology and Seismology (Phivolcs) was established, her family had been relying on animal behavior to indicate when Mayon would blow its top.

The past few days, wildlife has been restless along the slopes, said Solano, who grew up in Antoling?s neighboring village within the 6-kilometer permanent danger zone.

She said her family was already preparing for evacuation. ?That is why we are still alive today,? she said.

But Solano said she was still obeying the warning of government scientists. In fact, she said, the family has its own house at the town proper, which is far safer.

Although it is still unlikely that an eruption will happen within the next few days, resident volcanologist Eduardo Laguerta said Mayon continued to have earthquakes with five new episodes recorded during the past 24 hours.

Alert Level 2

Alert Level 2 still remains, meaning that the volcano is on a state of ?moderate unrest? that could eventually lead to a possible eruption. The 6-kilometer danger zone around Mayon and the 7-km danger zone in the southeast quadrant are still off-limits to the public.

Mayon has a sustained steaming activity, which was visibly high on Tuesday. ?The smoke plume rose from 200 to 500 meters and we are watching it closely,? Laguerta said.

Villagers living on the slopes and at the foot of Mayon said they had been hearing the rumbling sounds at night and witnessing intensifying crater glows, unusual drying up of wells, restive snakes crawling down the slopes.

They also smelled sulfurous substances.

Scientists at the Lingon Hill Observatory Center are keeping an open mind about these ?physical? manifestations.

?Changes in the environmental conditions of the habitat of animals drive them scampering and seeking for safe grounds when they sense a danger, especially on the upper slopes of the volcano,? Laguerta said.

The physical observations ?are also very helpful because animals are very sensitive and some of them have senses, peculiarly more sensitive than those of humans,? he explained.

Foul smell

?They could be experiencing suffocation and the foul smell of hydrogen sulfide and sulfur dioxide that are present near the crater, so they have to run for their lives, too,? he said. Hydrogen sulfide is highly flammable, he added.

Laguerta warned that if animals were fleeing the danger zones of Mayon, ?how much more the humans, who must not defy the warnings based on the combination of official scientific instruments and the physical observations??

Dioniso Oro, 76, who also lives along the volcano?s slopes in Mabalod, Guinobatan, said: ?We keep our eyes and ears keen to both the traditional observations and the advice of disaster authorities because each time Mayon erupts, our village is showered with ashes.?