Shikarpur, Pakistan (CNN) -- Dargahi Mirani is typically a fisherman by trade, but in the midst of devastating floods in Pakistan, local villagers have been turning to him not for his daily catch but for help in retrieving their loved ones' bodies from the floodwaters.
Mirani says he's lost count of how many he's found, estimating the number to be 16 or 17.
The death toll from the massive flooding has climbed to 1,639, but government officials say the number could rise substantially, as the floodwaters recede, and more bodies surface.
Aslam Noon knows the pain of those discoveries. On Sunday, he and several other relatives mourned four children, including Noon's own young son, from their family.
All four drowned in the receding waters after the family returned home from Karachi, where they had fled during the initial flooding weeks ago.
"I returned from Karachi to make my family safe and secure," Noon says, steps away from the four fresh mounds of dirt where the children lay buried. "I ran away from the floods. We just came back three or four days ago."
Samina Noon lost her only child -- an 8-year-old son.
"I had only one," she cries. "He was my life. I loved him so much."
While the Noon family grieves, others are still searching. Shaazadi Banglani says two of her children are missing.
"We tried to get out and I could only grab a few of my children," she says. "We couldn't grab two of them. They went in the water."
Maurizio Giuliano, a spokesman for the U.N. Office for the Coordination of Humanitarian Affairs, said Sunday that the floodwaters "continue to devastate Sindh (Province)."
"Even without counting what is being devastated just now, 1.7 million acres of crops are lost and over 200,000 livestock have died -- just in Sindh" in the country's south, Giuliano said.
"These figures are bound to rise in the coming days, once more data is available," he added.
More than 17 million Pakistanis -- about the population of the Netherlands -- have been affected by the monsoon floods that began a month ago.
At least 1 million people were displaced last week in Sindh, the United Nations said. Authorities issued evacuation orders after a levee burst.
And the effects of the floods will be felt for months, if not years to come.
Giuliano said Sunday that "among the affected population, 500,000 women are expected to give birth in the next six months, with 32,000 women expected to have complicated deliveries."
The United Nations and other countries and aid groups are actively working to assist with medical care and other relief efforts.
"Food from the (World Food Programme) has now reached 2.5 million people in need across the country, despite the immense logistical challenges posed by the number of people and vast area, and despite the shortage of helicopters, distributions are ongoing at the fullest possible speed," Giuliano said.
Clean water, however, remains a scarce commodity. Hundreds of thousands of victims have acquired transmittable ailments such as acute watery diarrhea, scabies and respiratory infections.
And while the waters have begun to recede across Pakistan, in the Indus River delta, the potential for more flooding remains high.